HELLO EVERYONE. WELCOME TO
THE NIH DNA REPAIR INTEREST
GROUP VIDEO CONFERENCE. TODAY WE
ARE HONORED TO HAVE A PROFESSOR
ALLEN LEHMANN. PROFESSOR LEHMANN
IS RESEARCH PROFESSOR FOR
MOLECULAR GENETICS, GENOME
DAMAGE AND DISABILITY CENTER
UNIVERSITY OF SUSSEX. HE
RECEIVED HIS BACHELORS DEGREE IN
CAME BRIDGE AND Ph.D. DEGREE
IN LONDON. HE -- DR. LEHMANN
HAVE LOT OF HONORS AND AWARDS,
INCLUDING THE FELLOWS OF ACADEMY
OF MEDICAL SCIENCES AND AND
FEDERAL SOCIETY OF BIOLOGY. HE
HAS ALSO BEEN AWARDED THE EU
PRIZE AND FIRST SOLO PRIZES OF
THE EUROPEAN ENVIRONMENTAL
SOCIETY. SO WITHOUT FURTHER
ADIEU, WE WILL HAVE THE STAGE TO
PROFESSOR LEHMANN FOR THE
AUDIENCE, PLEASE IF YOU HAVE ANY
QUESTIONS PLEASE TYPE IT IN THE
CHAT BOX AND WE WILL ELABORATE
AFTER THE TALK. THANK YOU.
PROFESSOR LEHMANN.
>> OKAY. THANK YOU VERY MUCH FOR
THE INTRODUCTION. I'M GOING TO
DIVIDE THE TALK INTO TWO REALLY
UNCONNECTED PARTS. THE FIRST
PART WILL BE A HISTORY OF
TRANSLESION SYNTHESIS, FROM THE
YEARS 1968 TO 1999. AND THEN FOR
THE REST OF THE TALK I'M GOING
TO BE TELLING YOU ABOUT THE
MULTI-DISCIPLINARY CLINIC XP
SYNDROME TTD IN THE UK AND FOCUS
ON TWO CASES WHICH WILL BE OF
PARTICULAR INTEREST. SO TO START
WITH TRANSLATION SYNTHESIS, I'M
GOING BACK TO ANCIENT HISTORY
FROM 1968 TO 1980. 1968 WAS A
SEMINOLE YEAR IN THE DNA REPAIR
FIELD FOR TWO MAJOR DISCOVERIES.
THE FIRST ONE WAS BY JAMES
CLEAVER, SHARING XP CELLS INTO
MUTAGEN (INAUDIBLE) SO CLEAVER
IN 1968 PUBLISHED A PAPER
SHOWING FIBROBLASTS FROM XP
PATIENTS AFTER UV. THE
EXPERIMENT WAS TO TAKE NORMAL OR
XP CELLS UV IRRADIATE THEM AND
INCUBATE THEM IN THE HEAVY
ANALOG PROXY URIDINE AND
SEPARATE DNA ON THE BASIS OF
ENTITY ON THE SODIUM CHLORIDE
GRADIENT. I WON'T GO INTO
DETAILS OF THE -- HOW THE
EXPERIMENT WORKS, ALL YOU NEED
TO KNOW IF YOU SEE A SOLID BAND
THIS POSITION HERE YOU HAVE
REPAIR SYNTHESIS. NORMAL CELLS
NO UV, NO EVIDENCE OF ANY
REPAIR. LOW DOSE UV YOU BEGIN TO
SEE HINT OF A PEAK HERE THEN
HIGHER DOSE UV, A CLEAR CLEAR
PEAK HERE INDICATING YOU HAVE
REPAIR SYNTHESIS IN NORMAL HUMAN
FIBROBLASTS. CONTRAST THIS WITH
XP FIBROBLASTS WHERE ZERO LOW
DOSE OR HIGH DOSE OF UV YOU FIND
NO TRACE OF REPAIR SYNTHESIS. SO
THIS IS THE FIRST EVIDENCE THAT
XP CELLS ARE DEFICIENT IN WHAT
WE NOW CALL NER. THE SECOND
DISCOVERY WAS POST REPLICATION
REPAIR, (INAUDIBLE) IN YALE
PUBLISHED IN IN THE SAME YEAR.
SO THE EXPERIMENT HERE YOU TAKE
E. COLI CELLS, UV IRRADIATE
THEM, TIME DEAN AND FOLLOW WITH
A CHASE OF COLD THYMADINE NOW
SEPARATION IS ON THE BASIS OF
SIZE. (INAUDIBLE) RIGHT TO LEFT
SO BIG DNA ON THE LEFT, SMALL
DNA ON THE RIGHT. IN
UNIRRADIATED CELLS, THE PULSE
LABEL SHIELDED ALL THE DNA WAS
BIG SO NEARLY SYNTHESIZED DNA
WAS PRETTY BIG SIZE. HOWEVER,
AFTER CELLS FOR UV IRRADIATED
THE NEWLY SYNTHESIZED DNA WAS
SMALLER AS YOU CAN SEE HERE.
THEN IF YOU INCUBATE FURTHER THE
SMALL DNA BECAME BIG. THEY
PROPOSE WHAT WAS HAPPENING IS
DNA WITH PHOTO PRODUCT IN THE
NEWLY SYNTHESIZED DNA, GAPS WERE
LEFT OPPOSITE THE (INAUDIBLE).
AND THE TRACE INDICATED THE GAPS
WERE SOMEHOW SEALED BUT AT TIME
NO INDICATION WHAT THE MECHANISM
MIGHT BE. TWO OR THREE YEARS
LATER PUBLISHED ANOTHER PAPER
THEY SHOWED THE GAPS WERE FILLED
IN BY (INAUDIBLE) IN E. COLI. SO
HERE IS DAMAGE WITH A GAP
OPPOSITE IT AND DNA THAT SHOULD
GO IN HERE, THIS IS THE SAME
SEQUENCE AS IN THE PARENTAL DNA
OF THE SISTER DUPLEX SO
SUGGESTED AND PROVIDED EVIDENCE
THAT THERE WERE EXCHANGES
WHEREBY PARENTAL DNA AND NEWLY
SYNTHESIZED GOT SWAPPED INTO
NEWLY SYNTHESIZED DNA, THERE BY
REGAINING GENETIC INFORMATION.
SO IN 1972 I WAS DOING -- IN
1970, 71 I WAS DOING A POST-DOC
IN (INAUDIBLE) LAB AND I WANTED
TO SEE IF SIMILAR THINGS
HAPPENED IN MAMMALIAN CELLS.
THAT TIME I WAS USING MOUSE
CELLS. SO THIS IS THE EXPERIMENT
THAT I DID. HERE IS TWO REPLY
CONS THE SOLID LINES HERE ARE
PARENTAL DNA, THIS IS NEWLY
SYNTHESIZED DNA, X REPRESENTS
PHOTO PROBLEMS AND HERE ARE DNA
THAT IS LABELED WITH RADIATED
THIMADINE AND GAPS WERE LEFT
OPPOSITE THE PHOTO PRODUCTS JUST
LIKE IN E. COLI. SUBSEQUENT STEP
WAS TO INCUBATE WITH
DEOXIURIDINE. SO THERE ARE NOW
TWO POSSIBILITIES. IF THESE GAPS
ARE FILLED IN BY EXCHANGE AS IN
E. COLI THEN MATERIAL THAT GOES
IN HERE WOULD BE PARENTAL DNA
AND WOULD NOT CONTAIN THERMO
DEOXIURIDINE. ON THE OTHER HAND
IF GAPS WERE FILLED BY WHAT WE
NOW CALL SYNTHESIS, THERE WOULD
BE FILLED IN WITH DEOXIURIDINE
INDICATED BY THESE BLACK BLOCKS
SO THE (INAUDIBLE) LAB WAS
MAKING USE OF TECHNOLOGY AT THAT
TIME WHEREBY DEOXIURIDINE
SUBSTITUTED DNA IF YOU
IRRADIATED IT AT 313 NANOMETERS
HIGH DOSE, THAT PRODUCED BREAKS
IN BROMODEOXIURIDINE SUBSTITUTED
DNA BUT NOT IN DNA THAT CAME
WITH THIMADINE LABELED SO IN
THIS CASE ON THIS SCENARIO 313
NANOMETER IRRADIATION WOULD NOT
BREAK THIS DNA BECAUSE IT WAS
THIMADINE LABELED THE PARENTAL
DNA FROM THE SISTER DUPLEX. ON
THE OTHER HAND TRANSLATED
SYNTHESIS IRRADIATION WOULD GROW
WITH 313 NANOMETERS TO REFORM
GAPS INDICATED HERE. INDEED WITH
WHAT I FOUND, IT APPEARED LIKE
GAPS WERE BEING FILLED IN BY
TRANSLESION SYNTHESIS AND NOT
LIKE SISTER TRANSEXCHANGES FOUND
IN E. COLI. AGAIN WE HAD NO
INFORMATION AS TO HOW THIS
TRANSLESION SYNTHESIS MIGHT TAKE
PLACPLACE. I DO RECALL IN 1971
SUGGESTING THERE MIGHT BE A DNA
POLYMERASE THAT COULD SYNTHESIZE
ACROSS THAT BUT THAT WAS
REGARDED AS RATHER A LUNATIC
IDEA UNFORTUNATELY I NEVER
PUBLISHED IT SO I CAN'T GET ANY
CREDIT FOR IT. MOVING ON ABOUT
THE SAME TIME, DISCOVERY OF XP
VARIANTS BY THE LAB OF JAY
ROBINS OVER THERE WITH NIH. THIS
IS TAKEN FROM ROBINS AND KRAMER
REVIEW IN 1974. WHAT THEY ARE
SHOWING HERE IS THIS XP VARIANT
PATIENT HAD VERY SIMILAR
CLINICAL FEATURES TO THE XPC
PATIENT INDICATED NEXT DOOR. IN
FACT HAD MORE THAN 100 SKIN
CANCERS AND DIED AT AGE 27. BUT
IN CONTRAST TO THE XPC, THESE XP
CELLS HAD NORMAL UDS. SO WHAT
WAS GOING ON HERE? SO NOW
UNIVERSITY OF SAW SEX I SET UP
MY OWN LAB AND -- SUSSEX. XP
VARIANTS WE WANTED TO SEE IF
THEY WERE IN THE REPAIR PROCESS.
SO THE EXPERIMENT WAS TO UV
IRRADIATE POST LABEL RADIATED
THIMADINE AND CHASE AGAIN WITH
OR CUT CAFFEINE SO THEY ARE
SHOWN TO SYNTHESIZE CERTAIN
CELLS TO IRRADIATION BUT
COULDN'T THINK OF ANYTHING ELSE
TO DO CHUCKING CAFFEINE TO SEE
CHAPS. THIS PROVED TO BE
PROFITABLE ON THIS OCCASION.
THIS IS AN ALKALINE SUCROSE
GRADIENT, SODIUM FROM RIGHT TO
LEFT, BIG DNA ON THE LEFT. IN
NORMAL CELLS WE FOUND THE POST
LABEL DNA AT THE UV IRRADIATION
WAS SPREAD ACROSS THE GRADIENT.
DISTRIBUTION OF DIFFERENT SIZES.
WHEN WE INCUBATED IN THE CHASE,
ALL THE DNA BECAME BIG AS YOU
CAN SEE BY THE SOLID LINES HERE.
ADDING CAFFEINE INDICATED BY THE
THATCHED LINES HAVE NO EFFECT
WHATSOEVER. CONTRAST THAT WITH
THE XP VARIANT CELL LINE DOWN AT
THE BOTTOM HERE. WE SHOW NEWLY
SYNTHESIZED DNA AND NEWLY
IRRADIATED CELLS MUCH SMALLER
THAN NORMAL CELLS. FURTHER
INCUBATION IT SLOWLY GOT BIGGER
AND PUTTING IN CAFFEINE HERE HAD
DIRECT EFFECT SMALL EFFECT IN
THE PULSE BUT COMPLETELY
INHIBITED CONVERSION OF LOW TO
HIGH MOLECULAR DNA SHOWING THE
VARIANTS HAVE A DEFECT IN WHAT
WAS CALLED POST REPLICATION
REPAIR. COUPLE OF YEARS LATER
VERONICA MARS GROUP LOOKED AT
THE UV OF XP VARIANTS. CELL
KILLING FUNCTION OF UV NORMAL
LINE AND XP VARIANT LINE, NOT
PARTICULARLY SENSITIVE COMPARED
TO DEFECTIVE XPs WHICH GIVE A
LINE HERE. HOWEVER, IF THEY
LOOKED AT MUTABILITY HERE IS
NORMAL UV MUTABILITY AND VARYING
LEVEL OF MUTABILITY AND THEY ARE
DEFECTIVE XP. SO HERE WE HAVE A
VERY NICE CORRELATION BETWEEN
THE UV HYPERMUTABILITY AND THE
SUSCEPTIBILITY TO INDUCE --
SUNLIGHT INDUCED SKIN CANCERS.
SO VERY PRODUCTIVE PERIOD IN
THIS AREA IN THE 19TH, LATE
1960s AND 1970s BUT THEN IN
1980ESS WE ENTERED THE DARK
AGES, NOTHING MUCH HAPPENED OVER
THIS PERIOD IN THIS AREA OF POST
REPLICATION REPAIR TRANSLESION
SYNTHESIS. NOW WE HAVE TO GO
BACK A FEW YEARS AND LOOK AT THE
ROLE OF MECHANISM OF UV
MUTAGENESIS IN E. COLI. SO THE
UNUC AND D GENES SHOWN REQUIRED
FOR THE UV MUTAGENESIS IN E.
COLI AS PART OF THE SOS
RESPONSE. IN THE 1980s A90s
THE ROLE WAS THOUGHT TO BE
LOWERING THE STRINGENCY OF POLL
3 TO ENABLE IT TO CARRY OUT
TRANSLESION SYNTHESIS. SHOWING
YOU THIS PICTURE TWO IMPORTANT
PEOPLE INVOLVED IN THIS WORK.
THIS IS BEN BRIDGES HERE, THIS
HANDS SOME YOUNG FELLOW I THINK
IS ONLINE TODAY, THAT IS ROGER
WOODGATE. WHEN HE WAS DOING A
Ph.D. WITH BRAIN AT THE TIME.
SO THEN MOVING ON TO THE
BIOCHEMISTRY OF UMUC AND D WHAT
DO THEY DO? FIRST BIT OF
INFORMATION I WANT TO GIVE YOU
IS THEY FOUND SOS INDUCTION
RESULTS IN CLEAVAGE OF END
TERMINAL 24 AMINO ACID THE UMUD
PROTEIN. THESE THREE LABS SHOWED
THAT. BEN ROGERS WITH PATRICK
SHOWED THERE WAS COMPLEX FORMED
OF TWO MOLECULES OF UMUD PRIME
THE CLEAVED FORM OF UMUD AND
MOLECULE OF UMUC. SUBSEQUENTLY
ROGER AND GOODMAN'S LAB PURIFIED
THIS PRIMER. THEN AFTER THIS
RATHER MANY YEARS WHERE VERY
LITTLE HAPPENED THERE WAS A
MAJOR REVOLUTION IN 1999, THE
YEAR OF THE NEW POLYMERASES. SO
LET'S GO THROUGH DRAMATIC EVENTS
THAT HAPPENED IN THIS AREA JUST
IN ONE YEAR. (INAUDIBLE) WAS
IDENTIFIED AS A DNA POLYMER RACE
POL 4 RELATED TO UMUC AND 30 BY
GROUPS OF FOX AND M NOMI. IN
1999, THREE GROUP -- TWO GROUPS
FOUND UMUD PRIOR TO C WHAT IN
FACT DNA POLYMERASE WE NOW KNOW
AS POLV AND SHOWED POL 5 CAN
CARRY OUT TRANSLESION SYNTHESIS.
MOVING UP TO YEAST. ROGER'S
GROUP AND CEDAR'S GROUP
IDENTIFIED SEQUENCE IDENTITIES
BETWEEN (INAUDIBLE) 30 IN YEAST
AND THE E. COLI GENES THAT
INDICATED HERE. IN 30 BEGINNING
OF THE YEAR WAS FINALLY FOUND TO
BE DNA POLYMERASE BY THE PRAKASH
GROUP. ANOTHER DEVELOPMENT IN
THE SAME YEAR, WAS THE
DEVELOPMENT OF IN VITRO SYSTEMS
WHICH WERE ABLE TO MIMIC THE
DEFECTED XP VARIANTS. THE
EXPERIMENT HERE IS TO TAKE --
SELL EXTRACTS AND OFFER THEM
PLASMID CONTAINING A SINGLE
LESION. THEN LOOK AT THE ABILITY
OF DIFFERENT EXTRACTS TO
REPLICATE PAST DAMAGE IN THESE
SUBSTRATES. HERE YOU CAN SEE ONE
SUCH EXPERIMENT, THIS IS A
RESULT OF (INAUDIBLE) LAB, SO IN
NORMAL EXTRACTS, YOU CAN SEE
HERE THE TRANSLATION SYNTHESIS
GIVES THE BAND AT THIS POINT
(INAUDIBLE). IF YOU LOOK AT XP
VARIANT EXTRACTS HOWEVER, THEY
STOPPED BLOCKED AT POSITION OF
VERY LITTLE TRANSLATION
SYNTHESIS. THIS IS MORE -- SAME
RESULT WITH SLIGHTLY DIFFERENT
LESION. SO USING ONE OF THESE
SYSTEMS, (INAUDIBLE) GROUP
PURIFIED THE PROTEIN THAT WAS
DEFECTIVE IN XP -- THE EXTRACT
SEQUENCE PEPTIDE SCREEN LIBRARY
AND IDENTIFIED THE GENE AND
FOUND MUTATIONS IN XPV PATIENTS
FROM THIS PROTEIN WAS DNA
POLYMERASE WHICH WE NOW KNOW IS
(INAUDIBLE) HERE IS CRUCIAL
EXPERIMENT, CRUCIAL RESULTS FROM
THAT WORK SO THEY ARE USING AN
OLIGONUCLEOTIDE SUB INVESTIGATE
WITH A SINGLE PYRIMIDINE DIMER
HERE. WITHOUT DAMAGE BOTH
PAULETTEA AND (INAUDIBLE)
SYNTHESIZE RAD 30 NUCLEOTIDE,
WHEREAS IF THERE IS A PYRIMIDINE
DIMER HERE, YOU CAN SYNTHESIZE
POL ALPHA IS BLOCKED AT THE
LESION. THE MORE I
SIMULTANEOUSLY PRAKASH GROUP RAD
30 HOMOLOGUE AND FOUND HOMOLOGUE
FROM THE GENE AND FOUND IN XPV
PATIENTS AS WELL. SO CLEARLY
PAULITA WAS A GENE PRODUCT
LACKING IN XP VARIANTS. ROGER
AND COLLEAGUES FOUND THE SECOND
RAD 30 HOMOLOGUE, CALLED
(INAUDIBLE) NOT FOUND TO BE
MUTATED IN XP VARIANT PATIENT.
LIKEWISE WAS A HOMOLOGUE WE KNOW
AS POL KAPPA BUT HUMAN RED 1
HOMOLOGUE ALSO BEEN IDENTIFIED.
SO THIS RATHER STUNNING SERIES
OF PAPERS ALL IN 1999, IF YOU
LOOK BETWEEN JULY AND AUGUST --
BETWEEN JUNE AND AUGUST, FIVE
PAPERS XPV PROTEIN BEING
HOMOLOGOUS TO RAD 30 BY THESE
TWO GROUPS, UMUD THROUGH C POL 5
PNAS AND HOMOLOGUE DNA
POLYMERASE FORM. SO THE
ASTONISHING YEAR WHICH REALLY
COMPLETELY OVERTURNED THE
TRANSLESION SYNTHESIS FIELD AND
THAT IS WHERE I'M GOING TO LEAVE
IT BECAUSE THE REST IS MODERN
HISTORY AND I'M SURE MOST OF YOU
KNOW THE DETAILS OR MANY OF THE
DETAILS THAT HAVE BEEN GOING ON
SO NOW I'M GOING TO CHANGE TRACK
COMPLETELY. AND MOVER TO TELL
YOU ABOUT THE MULTI-DISCIPLINARY
CLINICS THAT WE HAVE ESTABLISHED
IN THE UK. THE FIRST IS THE UK
MULTI-DISCIPLINARY CLINIC.
EXCUSE ME A MOMENT. ESTABLISHED
BY MY DERMATOLOGY COLLEAGUE IN
2010, WE NOW HAVE 120 XP
PATIENTS PRETTY MUCH ALL THE XP
PATIENTS IN THE UK VISITING ON A
REGULAR BASIS. TYPICALLY ONCE A
YEAR BUT IN SOME CASES MORE
OFTEN IF THEY NEED MOB
WOKSMEMORE WOR WORK.CRUCIAL ROLN
AT THE BOTTOM HERE I'M VERY MUCH
PART TIME CONSULTANT SCIENTIST.
SO HERE IS A DISTRIBUTION OF
DIFFERENT COMPLEMENTATION
GROUPS. 22 XPA WHICH DIVIDED TO
TWO GROUPS WILL BECOME CLEAR IN
A MOMENT. JUST ONE XPV, NONE OF
XPC, FAIR NUMBER OF DNA
VARIANTS, EF AND G, SIMILAR TO
WHAT OTHER GROUPS REPORTED IN
OTHER -- IN DIFFERENT PARTS OF
THE WORLD. OF THE WEST.
COMPLETELY DIFFERENT IN JAPAN.
LET'S LOOK AT THE XPA PATIENTS.
LOOK A AT LINE HERE YOU SEE 8 OR
9 XPA PATIENTS WHICH ARE
TEXTBOOK PATIENTS, VERY SEVERE
THEY TYPICALLY GOT TRUNCATION
MUTATION. NEUROLOGISTS DEVELOPED
A NEUROSTORE WITH A MAXIMUM OF 8
YOU CAN SEE THEY HAVE SEVERE
NEUROLOGICAL ABNORMALITIES,
THEIR AGE IS OVER HERE. SO THIS
IS WHAT YOU CAN READ IN MANY
EARLIER PAPERS. CONTRAST THAT
WITH THE ONES BELOW THE LINE.
NONE HAVE NEUROLOGICAL PROBLEMS.
THEY ALL HAVE THE SAME MUTATION.
OF THE 8 BASE INTRON 4 AND A TO
JJ. HERE IS ONE OF THE FIRST ONS
MISDEMEANOR WERE SUN SORNED WORK
OUTDOORS AS A (INAUDIBLE) UNTIL
HE MOVEDDED TO THE UK AT AGE 32.
DIDN'T HAVE ANY SKIN CANCER
UNTIL 65, NO NEUROLOGY AT ALL,
HE DIED A COUPLE OF YEARS AGO IN
HIS '80s. HERE ARE THREE MORE
WITH RELATIVELY MINOR SKIN
PROBLEMS, NO SKIN CANCER, NO
NEUROLOGY, EVEN THOUGH THEY
DON'T PROTECT THEMSELVES PRETTY
WELL. SO WHAT IS GOING ON HERE?
ALL THESE INDIVIDUALS COME FROM
THIS AREA OF NORTHERN INDIA,
NORTHERN PAKISTAN AND
AFGHANISTAN. SUGGESTING STRONGLY
THERE IS A FOUNDER EFFECT AT
THAT LOCATION. SO WHAT IS GOING
ON? THE SPLICE MUTATION
INDICATES WHY THEIR UDS IS LOW.
AND THIS MUTATION GENERATES A
NEW (INAUDIBLE) FROM THE 8TH
BASE HERE WHICH RESULTS IN THE
INSERTION OF SEVEN BASES BETWEEN
EXON 4 AND 5 WHICH IS WHAT IS
THE SEQUENCE -- PUTS THE
SEQUENCE OUT OF FRAME AND
RESULTS IN A SEVERERY TRUNCATED
PROTEIN. SO WHY THE SYMPTOM IS
SO MILD, WE FOUND IT WAS
APPROXIMATELY 5% OF NORMAL
MESSENGER RNA BEING MADE. WHEN
WE WENT TO FURTHER AND LOOK AT
XPA PROTEIN, WE GOT RESULTS
HERE. ON THE LEFT-HAND SIDE WE
HAVE CALIBRATION OF INCREASING
AMOUNTS OF NORMAL EXTRACT. ON
THE RIGHT HAND SIDE WE HAVE 50
MILLIGRAMS OF EXTRACT FROM
NORMAL INDIVIDUALS BOTH FROM XPA
PROTEIN. ON THE RIGHT HAND SIDE
WE HAVE XPA NULL WITH NO BANDS
IN THIS POSITION BUT FOUR OF
THESE WITH THE INTRON MUTATION
YOU CAN SEE SMALL AMOUNTS OF XPA
PROTEIN MADE CORRESPONDING TO 5%
OF XPA PROTEIN. IF WE LOOK MORE
CAREFULLY AT SCHEDULE DNA
SYNTHESIS, NORMAL RESPONSE XPA
NULL YOU CAN SEE A SMALL AMOUNT
OF UNSCHEDULED DNA SYNTHESIS IN
THESE INDIVIDUALS WITH XPA
INTRONNIC MUTATION. SO IT SEEMS
THAT IN XPA THE VERY LOW LEVEL
OF RESIDUAL REPAIR IS SUFFICIENT
TO ALLEVIATE NEUROLOGICAL
PROBLEMS AND MANY OTHER SKIN
PROBLEMS AS WELL. SO WE HAVE
DEFINITIVE EVIDENCE HERE THE
LIFE MUTATION LEAVING IN SMALL
AMOUNT OF NORMAL SPLICING CAN
GIVE RELATIVELY MILD SYMPTOMS.
AND KRAMER ALSO REPORTED SIMILAR
THINGS WITH AN XPC PATIENT. WE
HAVE SEVERAL OTHER PATIENTS WE
THINK WE MIGHT SEE THE SAME --
BE SEEING THE SAME THING IN
DIFFERENT XP GROUPS BUT WE DON'T
HAVE COMPLETE DEFINITIVE
EVIDENCE INDICATED HERE. NOW
MOVING TO XPD. HERE IS THE TWO
INDIVIDUALS SIMILAR AGE, AGE 25,
IN THIS CASE 19, BOTH HAD SEVERE
SUNBURNS FROM BIRTH BUT THEY
HAVE BEEN REALLY FANTASTICICALLY
WELL PROTECT SOD THEY HAVE NO
SKIN LESIONS AT ALL. THE ONE ON
THE LEFT HAD RECURSIVE
NEUROLOGICAL DISEASE FROM AGE 7
YOU CAN SEE THE SYMPTOMS HERE.
HE SADLY DIED A FEW YEARS AGO
AGE 28. THIS YOUNG MAN NOW ABOUT
THE SAME AGE, 28 HAS HAD NO
NEUROLOGICAL PROBLEMS AT ALL. IF
WE LOOK AT MUTATIONS, THEY
MUTATED AT THE SAME AMINO ACID
ARGININE 683. IN THIS CASE A
TRYPTOPHAN BUT IN THIS CASE
GLUTAMINE. HERE IS ONE OF THE
3-D STRUCTURE OF THE XPD
PROTEIN. THIS ONE GENERATED BY
THE (INAUDIBLE) GROUP, ARGININE
683 DOWN HERE. BUT IF WE FOCUS
IN ON ARGININE 683 WE SEE HERE
IT HAS INTERACTIONS WITH
ASPARTATE 681 WHERE THE DNA IS
INDICATED BY THIS PURPLE LINE.
SO HERE IS ARGININE AS A
BIOCHEMIST AMONG YOU OBVIOUSLY
KNOW. THIS IS GLUTAMINE WHICH
YOU CAN SEE IT IS SMALLER, IT IS
NEUTRAL AS OPPOSED TO ARGININE
WHICH IS POSITIVELY CHARGED BUT
IT IS HYDROPHILIC AND PROBABLY
SIT IN HERE QUITE COMFORTABLY
WITH SOMEWHAT WEAKER
INTERACTIONS. THIS IS THE
MUTATION, MUTATED AMINO ACID IN
THE YOUNG MAN ON THE RIGHT WITH
NO NEUROLOGICAL PROBLEMS. WHERE
TRYPTOPHAN AROMATIC SIDE CHAIN
IS LIKELY TO BLOW THIS AREA
APART AND PROBABLY ACCOUNTS FOR
WHY MORE SEVERELY AFFECTED YOUNG
MAN HAD THOSE SEVERE
NEUROLOGICAL PROBLEMS. NOW, A
FEW WORDS ABOUT XPF. WE HAVE
SEVERAL XPF PATIENTS, THEY ARE
ALL NOT THAT YOUNG BUT NONE HAD
ANY SKIN CANCERS EVEN THOUGH
THEY HAVEN'T NECESSARILY BEEN
THAT WELL PROTECTED. HERE ARE
TWO OF THEM, YOUNG MEN. NOW A
FEW YEARS OLDER. THEY BURN
EASILY, TAKING TWO WEEKS TO
RESOLVE REASONABLE BUT NOT
RIGOROUS PROTECTION BUT THEY
HAVE VERY FEW SKIN CHANGES, SOME
YOU WOULDN'T THINK HAD XP AT
ALL. NO NEUROLOGICAL PROBLEMS AT
ALL. THIS LADY, EXAGGERATED
SUNBURN, YET SOME SUN PROTECTION
BUT SHE WASN'T DIAGNOSED UNTIL
SHE WAS 29. SHE HAD NO SKIN
CANCER U YOU CAN SEE HER SKIN
FEATURES ARE RELATIVELY MIL MILN
HER LATER LIFE SHE DEVELOPED
PROGRESSIVE NEUROLOGICAL
PROBLEMS AS YOU CAN SEE HERE,
DEAFNESS, DISABILITY, ATAXIA,
AND SHE SADLY DIED COUPLE OF
YEARS AGO FROM AN INTERNAL
TUMOR. SO THESE TWO YOUNG MEN I
SHOWED YOU A MINUTE AGO, MUTATED
AT PROLINE 379 TO SERINE. SO NO
NEURO ASSOCIATED WITH THOSE.
ARGININE 589 TO TRYPTOPHAN, THE
NO KNOWN MUTATION. THE ARGININE
799 THERE'S SEVERAL PATIENTS
REPORTED SEEM TO BE ASSOCIATED
WITH LATE ONSET NEUROLOGY. SO
YOU CAN ASSOCIATE DIFFERENT
MUTATIONS WITH DIFFERENT
CLINICAL PHENOTYPES. T I WANT TO
SAY A LITTLE BIT MORE ABOUT THIS
ONE. WE FOUND THIS MUTATION IN
THREE MILD XPF PATIENTS. AND
THIS ALTERATION IS THE IN THE
HUMAN SLIP DATABASE, YOU CAN SEE
OF NULL .3%. THE EVIDENCE OF
THAT IS FREQUENCY OF HOMOZYGOTES
IN THIS MUTATION IN THE
POPULATION IS 10 TO THE MINUS 5
SO THIS IS ABOUT FIVE TIMES
HIGHER THAN THE PRE-CONCEIVED HP
WESTERN EUROPE AND USA SO IN THE
UK PROBABLY ABOUT 500 TO 1,000
PEOPLE WITH THIS MUTATION
HOMOZYGOUS FOR THIS MUTATION.
AND WE JUST DON'T KNOW IF THEY
ARE JUST GOING TO BE SUN
SENSITIVE OR DEVELOP OTHER XP
SYMPTOMS LATER ON IN LIFE. I
SHOULD SAY THAT BEN KRAMERS
GROUP REPORTED DID A SIMILAR
ANALYSIS USING BIG DATA AND GOT
VERY SIMILAR RESULTS.MENT I
THINK CALCULATED SHOULD BE
SEVERAL THOUSAND INDIVIDUALS
HOMOZYGOUS FOR THIS MUTATION.
IN THE USA. NOW WE WILL FOCUS ON
TWO XP PATIENTS WHO HAVE GOT
SOME -- WITH RATHER REMARKABLE
FINDINGS. SO THIS IS A YOUNG
MAN WITH XPC, AND HE HAD THIS
VERY UNPLEASANT ANGIOSARCOMA
JUST ABOVE HIS EYE. IT WAS
EXTREMELY MALIGNANT AND RESULTED
IN NAY STASIS IN SEVERAL ORGANS
AND HERE YOU CAN SEE THIS BIG
CANCER ON THE SIDE OF HIS MOUTH
AND ACTUALLY HAD RECESSIVE IN --
METASTASIS IN MANY ORGANS. HE
WAS CLOSE WITHIN THREE WEEKS OF
DEATH. SO FROM ACADEMICALLY,
WHAT WOULD BE FOUND IN HIS
TUMOR. WE WERE COLLABORATING
WITH (INAUDIBLE) IN CAMBRIDGE
AND ASKED IF SHE WOULD BE
INTERESTED IN SEQUENCING THESE
TUMORS DNA WHICH SHE DID. AND
FOUND SOME REMARKABLE RESULTS.
THE OTHER THING SHE FOUND IS
EXTREMELY HIGH LEVEL OF
MUTATION. IF YOU TAKE IT WITH
MANY FOLD HIGHER THAN THE
HIGHEST BREAST CANCER TUMOR DNA
SHE HAD BEEN -- ANALYZED THE
WHOLE SEQUENCE AND SO THE
MUTATION FREQUENCY EXTREMELY
HIGH. AND WHAT HER SPECIALTY IS
IS LOOKING AT MUTATION
SIGNATURES. LOOK AT THE TYPES OF
MUTATIONS IN CANCER GENOMES
COMPARED WITH THE GENOMES --
COMPARED WITH THE GENOME WITH
THE SAME INDIVIDUAL IN THEIR
BLOOD. SO FINDINGS SHE MADE
FIRST OF ALL NOT VERY
SURPRISINGLY 91% HAD SIGNATURE 7
WHICH IS A SIGNATURE EXPECTED
FOR UV INDUCED MUTATION. MUCH
MORE INTERESTINGLY, SHE FOUND
THAT 9% HAD SIGNATURE 10.
SIGNATURE 10 IS ASSOCIATED WITH
DRIVER MUTATIONS IN THE
EXONUCLEASE DOMAIN POL EPSILON
AND FURTHER ANALYSIS THEY FOUND
INDEED A SERIES OF FEENAL
ALANINE CHAIN AT AMINO ACID 459
IN 17% OF THE TUMOR POPULATION.
SHE TOLD US HIGH MUTATIONAL
BURDEN AND SOMATIC MUTATIONS IN
POL EPSILON WERE YOU ARE THE
REPORTED PREDICTIVE OF
SENSITIVITY FOR IMMUNE CHECK
POINT INHIBITORS. NOW THERE WAS
A PROBLEM BECAUSE IMMUNE CHECK
POINT INHIBITORS ARE NOT
LICENSED OR NOT USED GENERALLY
FOR ANGIOSARCOMAS BECAUSE THEY
HAVEN'T BEEN EFFECTIVE. AFTER A
LOT OF DISCUSSION WITH
DERMATOLOGIST PERSUADED THE
ONCOLOGIST TO BE TREATED LIKE A
MELANOMA AND SHOULD BE TREATED
WITH THESE CHECK POINT
INHIBITORS. THE RESULTS BEFORE
DRAMATIC. AFTER A FEW WEEKS
TREATMENT YOU CAN SEE THIS BIG
TUMORS COMPLETELY GONE,
METASTASIS IN THE LIVER HAVE
COMPLETELY GONE. AND FIVE YEARS
ON THIS GUY IS DOING VERY WELL,
SERENA GAVE A TALK AT THE ROYAL
SOCIETY EARLIER THIS YEAR AND
THIS YOUNG MAN WAS SITTING NEXT
TO ME, SERENA TALKED ABOUT HIM
AMONG OTHER THINGS AND HE WAS TO
SOME EXTENT THE STAR OF THE SHOW
THERE. DRAMATIC ILLUSTRATION HOW
MOLECULAR ANALYSIS OF A TUMOR
CAN DIRECT THERAPY. SO NOW
JUMPING TO THE SECOND PATIENT,
MUCH MORE RECENTLY JUST A FEW
MONTHS AGO THE CLINIC, A
6-YEAR-OLD CHILD BROUGHT, FIRST
CHILD WITH UNRELATED HEALTH
PARENTS AND SHE HAD ALL THE
CLINICAL FEATURES OF XP, EXTREME
SUNBURN, PROGRESSIVE FACIAL,
FRECKLES IN THE FACE. SO WE
LOOKED AT SCHEDULE DNA
SYNTHESIS, CLEARLY CONSISTENT
WITH DIAGNOSIS WITH XP VERY MUCH
REDUCED. WHEN THE MOLECULAR
ANALYSIS WAS DONE BY OUR
COLLEAGUES IN (INAUDIBLE)
HOSPITAL USING A PLATFORM OF 14
GENES KNOWN TO BE DEFECTIVE IN
XP OR GGD, NO MUTATION WAS FOUND
IN ANY OF THE 14 NER GENES. SO
WE THEN CALLED ON MORE OF OUR
FRIENDS FROM A (INDISCERNIBLE)
IN JAPAN AND ASKED WOULD THEY BE
ABLE TO DO WHOLE GENOME
SEQUENCING OR EOME SEQUENCING TO
TRY AND FIND THE DEFECTIVE GENE.
THE ONLY THREE WHICH THEY CAME
UP WITH THE GOODS. SO THEY ALOUD
ME TO PRESENT SOME OF THEIR DATA
WHICH IS NOT YET PUBLISHED. SO
FIRST OF ALL THEY CONFIRMED OUR
FINDINGS WITH NO DEFECT IN ANY
OF THE KNOWN GENES SO THIS IS BY
LENTIVIRUS INFECTION WITH THESE
DIFFERENT CDNAs AND NONE OF
THE CORRECTED ON SCHEDULE DNA
SYNTHESIS THAT YOU CAN SEE HERE
IN ALL INDIVIDUALS. WHOLE
GENOME SEQUENCING IDENTIFIED
PATHOGENIC MUTATIONS IN THE GENE
GTF 2H 4 WHICH ENCODES THE P 52
SUB UNIT OF TF 28. YOU KNOW TF
28 CONTAINS HPD. THE XPD
PROTEIN. SO HERE WE HAVE A
MUTATION IN ANOTHER PROTEIN
COMPONENT OF TF 2H. MUTATIONS
THEY FOUND ONE IN THE SPLICED
RECEPTOR SIDE OF INTRON 2. WHICH
IS ALSO AN INFRAME COMPLETION
DELETION OF EXON 3 DEGRADED.
THE OTHER ONE A DELETION
INSERTION IN EXON 30 RESULTING
IN A TRUNCATED PROTEIN. WHICH
THEY FOUND WAS STABLE BUT
MISSING THE C TERMINAL 6D AMINO
ACIDS. SO HERE IS WESTERN BLOT
USING ANTIBODY TO P 52. HERE IS
THE FOUND IN NORMAL INDIVIDUALS
AND HERE THEY ARE FOUND IN XP 4
TFR IN THE PATIENT. THE FINAL
CONFIRMATION THIS WAS THE CAUSE
OF THE UV SENSITIVITY, THEY PUT
THE GTF 2 H POL GENE BACK WHERE
XP GENES NONE WERE ABLE TO
COMPLIMENT THE UNSETTLED DNA
SYNTHESSYNTHESIS. YOU CAN SEE HS
GENE COMPLIMENTED IT PROVING IT
WAS THE CAUSE OF THE DEFECTIVE
UV RESPONSE. SO SUMMARY SLIDES
TO THIS POINT. COMPLEMENTATION
GROUPS XPA TO G WERE IDENTIFIED
IN THE 1970s. SO NOW AFTER 44
YEARS WE HAVE A NEW
COMPLEMENTATION GROUP. WHAT MANY
OF YOU PROBABLY DON'T KNOW IS
THAT PATIENTS WERE ASSIGNED TO
GROUPS H AND I IN THE 1980s
BUT THAT WAS SUBSEQUENTLY FOUND
TO BE ERRONEOUS AND THEY WERE
RETRACTED. HOWEVER, IN ORDER TO
AVOID POSSIBLE CONFUSION WHICH
SUGGEST THE NEW COMPLEMENTATION
GROUP XPJ. THESE PATHOGENIC
MUTATIONS CAUSE A C TERMINAL
TRUNCATION OF THE P 52 SUB UNIT
AND AFFECT INTERACTIONS BETWEEN
P 52 AND TF 2H. SUBUNITS DAMAGE
AND EXCLUSIVELY AFFECT THE NER
ACTIVITY THAT DON'T AFFECT TRAN
-- THE OVERALL TRANSCRIPTIONAL
ACTIVITY, THIS IS ALSO WORK OF
TOMO AND YUKO WHICH I HAVEN'T
SHOWN YOU. SO SUMMARIZING THE XP
CLINIC WE FOUND A HUGE VARIATION
IN PHENOTYPE BETWEEN AND WITHIN
XP GROUP, COMPLEMENTATION GROUP
MOLECULAR ANALYSIS IS IMPORTANT
FOR PROGNOSIS AND I HAVE SHOWN
THE EXAMPLE OF THE XPA SPLICE
MUTATIONS AND THE XPD ARGININE
683 TRYPTOPHAN COMPARED TO
GLUTAMINE. I SHOWED YOU THAT XPA
SPLICE MUTATION IN RESIDUAL
ACTIVITY CAN AFFECT THE
PHENOTYPE DRAMATICALLY, THAT IS
PROBABLY ALSO TRUE WITH OTHER
GROUPS BUT WE NEED TO UPDATE AND
APPROVE THAT DEFINITIVELY. XPF I
SHOWED WITH XPV I HAVEN'T TALKED
ABOUT HAVE LOWER CANCER
PRE-DISPOSITION. WHY WE DON'T
KNOW AND THE QUESTION SHOULD IT
AFFECT MANAGEMENT OF THE
PATIENTS. I SHOWED YOU CASE
WHERE MUTATION ANALYSIS NAY MAY
DIRECT THERAPY AND THE NEW
COMPLEMENTATION GROUP XPJ. HERE
IS THE CLINICAL TEAM ON THEIR
ANNUAL RETREAT WHERE THEY
DISCUSS MATTERS OF INTEREST AND
FUTURE WAYS OF HANDLING HP
CLINICS IN THE FINAL TEN MINUTES
I WILL TELL YOU BRIEFLY ABOUT
THE (INAUDIBLE)
MULTI-DISCIPLINARY CLINIC
ESTABLISHED IN 2019 BY MY
CLINICAL GENETICS COLLEAGUE.
APPARENTLY WE HAVE 65 PATIENTS
ON THE BOARD. . THEY ARE SEEN
BY THESE SPECIALISTS AND AGAIN
I'M CONSULTANT SCIENTIST FOR
THIS CLINIC. IT IS IN RARE
DISEASE CENTER SAINT THOMAS
HOSPITAL IN LONDON. SO HERE IS A
SUMMARY OF THE PATIENTS, 34
CAUCASIAN PATIENTS WHICH ABOUT
ONE-THIRD CSA AND TWO-THIRDS CSB
IS SEEN IN SEVERAL OTHER
STUDIES. WE HAVE 7 INDIVIDUALS
WE CLASSIFY AS (INAUDIBLE)
SYNDROME LIKE. WE HAVE 17 BE TTD
MOST WHICH ARE MUTATED IN XPV
BUT COUPLE IN TTDA, COUPLE IN
TTN 1, WE HAVEN'T YET BEEN ABLE
TO ASSIGN TO A PARTICULAR GENE.
RECENTLY THE CLINIC STARTED
TAKING ON BLOOM SYNDROME, NOT
REALLY I'M NOT INVOLVE THIRD
DEGREE IN THAT AND I WILL ONLY
TALK ABOUT CS AND CS LIKE
INDIVIDUALS TODAY. SO FOR THOSE
OF YOU NOT THAT FAMILIAR WITH
COCAINE SYNDROME, HERE IS THE
CLINICAL FEATURE GROWTH FAILURE
CATARACTS, HEARING LOSS, PHOTO
SENSITIVITY, DENTAL ISSUES
SPEECH ISSUESS. SENSITIVITY TO V
WHICH WE DETECT USING THE ROS
TEST, ROS FOR RECOVERY OF RNA
SYNTHESSYNTHESIS. WIDE SPECTRUMF
PHENOTYPES, MOST OF THEM SADLY
DIE MANY THE FIRST OR SECOND
DECADE, IT IS A VERY SEVERE
DISORDEORDER. THERE ARE ONE OR O
EXCEPTIONS, THIS IS A LADY THAT
CAME TO CLINIC AGE 52 WITH
COCKYNE SYNDROME. THE PROTRUDING
TEETH AND DEEP SET EYES. SHE
HAS A MUTATION HETEROZYGOUS 11
TRUNCATION MUTATION. AND
INTERESTINGLY THE OTHER ONE IS A
SPLICE MUTATION. SO WE WONDER IF
MAKING A SMALL AMOUNT OF NORMAL
PROTEIN. HOWEVER, WHEN WE LOOK
IN OUR RS TEST WE DON'T SEE ANY
DIFFERENCE BETWEEN THE UV
SENSITIVITY OF HER CELLS AN
THOSE OF THE MUCH YOUNGER
PATIENTS WITH MORE NORMAL
SYMPTOMS AT A YOUNG AGE. SO FEW
SLIDES ABOUT COCKAYNE LIKE
PATIENTS. THE FIRST WAS THIS
YOUNG LADY WHO HAD MANY COCKAYNP
FEATURES DELAYED MOTOR
DEVELOPMENT, THIS MORPHIC
FEATURE -- DISMORE IF I CAN
FEATURES DEEP SET EYES BUT SHE
WASN'T PHOTOSENSITIVE. WHEN WE
DID THE ROS TEST IT WAS
COMPLETELY NORMAL. SO IN
COLLABORATION BETWEEN
(INAUDIBLE) LAB, AND JEGGO LAB
AND OUR LAB DID WHOLE EXOSOME
SEQUENCING AND FOUND MUTATIONS
IN THE XRCC 4 GENE, COMPOUND
HETEROZYGOTES LEADING TO
TRUNCATIONS. IF YOU LOOK AT
WESTERN BLOT USING ANTIBODY
DIRECT RCC 4 HERE IS FOUND IN
NORMAL INDIVIDUALS, ANOTHER --
SORRY HERE IS BAND IN NORMAL
INDIVIDUALS, BUT IN SIMILAR
AMOUNT EXTRACT FROM THIS
INDIVIDUAL YOU SEE NO TRACE OF
XRCC 4. XRCC 4 IS KNOWN
ESSENTIAL GENE SO WE SUSPECT
THERE MUST BE A SMALL AMOUNT AND
WE KNOW IT IS POSSIBLE TO DETECT
A VERY SMALL AMOUNT LESS THAN 5%
OF XRCC 4 BUT THAT SEEMED
SUFFICIENT FOR THIS YOUNG LADY
TO SURVIVE WITH THESE -- UNTIL
SHE WAS 26 OR 27 WHEN SHE SADLY
DIED A COUPLE OF YEARS AGO. SO
TWO -- ONE OTHER REMARKABLE
POINT WE PUBLISHED THIS WORK IN
2015 UP TO 2014, NO XRCC 4
PATIENTS IDENTIFIED OR REPORTED
IN 2014, 15, THERE WERE 6 PAPERS
REPORTING DRCC 4 PATIENTS
INCLUDING ONE FROM ANDREW
JACKSON'S LAB IN EKNBORO. AND
AGAIN, IT WAS ANOTHER EXAMPLE OF
EVERYTHING HAPPENING THE SAME
YEAR. I HAVEN'T BEEN ABLE TO
FIND ANY FURTHER REPORTS OF XRCC
4 PATIENTS. SINCE 2015. TWO
(INAUDIBLE) TURNED UP AT OUR
CLINIC. THIS IS ONE OF THEM. THE
MOST DRAMATIC FEATURE IS THIS
SEVERE GROWTH DELAY. THIS YOUNG
MAN HERE, HE'S FIVE YEARS OLD.
AND YOU CAN SEE HERE HE IS
ABSOLUTELY TINY. COGNITIVE
DEVELOPMENT DELAY BUT HE RUNS
AROUND QUITE HAPPILY, HE DOESN'T
SPEAK BUT HE HAS THESE COCKAYNE
FEETURES YOU CAN SEE THE
COMPOUND HETERO ZYGOTES AND THE
PREVIOUS PATIENT YOU MENTIONED
AND THIS YOUNG MAN ARE SENSITIVE
TO IONIZING RADIATION AND
DEFICIENT IN DOUBLE STRAND BREAK
REPAIR AS YOU EXPECT BECAUSE
XRCC 4 IS CO-FACTOR FOR DNA
LIGASE KNOWN TO BE INVOLVED IN
DOUBLE STRAND BREAK REPAIR FOR
MANY YEARS. THIS IS SURVIVAL
AFTER IONIZING RADIATION NORMAL
INDIVIDUALS AND HERE IS PATIENT.
THIS WORK IS DONE BY MY
COLLEAGUE LISA WOODBONE. SO
PETER CANE'S LAB IN IN FLORIDA
HAD SHOWN THEY ALSO HAD SOME
COCKAYNE LIKE PATIENTS AND
PICKED ORAL 2 MUTATIONS
(INAUDIBLE) WE HAVE HALF DOZEN
PATIENTS BUT WE THOUGHT LOOKED
VERY MUCH LIKE COCKAYNE PATIENTS
BUT NORMAL ROS AND DIDN'T HAVE
MUTATIONS IN THE CSA OR CSB
GENES SO WE SENT THE CELLS TO
PETER'S LAB AND HE FOUND THAT
THREE OF THEM HAD MUTATIONS IN
THE SAME GENE, MORC 2. SO HERE
IS A COUPLE OF SIBLINGS THEY
FOUND MUTATED IN THAT GENE. SO
THE CLINICAL FEATURES AGAIN,
SIMILAR FOR COCKAYNE, SHORT
STATURE GATE DISTURBANCE
ABNORMAL TENDON REFLEXES,
TREMORS AND INTELLECTUAL
DISABILITY. NO MUTATION, CS
GENES NORMAL RECOVERY OF RS AT
THE U -- AFTER UV. THEY HAD DE
NOVO HETEROZYGOUS MUTATION IN
MOCR 2 GENE KNOWN TO BE DOMINANT
SO THESE TWO INDIVIDUALS
MUTATION IS MISSENSE MUTATION
ALANINE TO AND TORR SCENE TO 3
ANINE. WHAT IS MORC 2?
TRANSCRIPT -- ROLES IN
TRANSCRIPTION REGRESSION, DNA
DAMAGE RESPONSE IN METABOLISM.
IT IS ASSOCIATED WITH TWO OR
THREE OTHER DIFFERENT DISORDERS
SO THIS IS FROM A REVIEW LAST
YEAR SHOWING THE ROLES OF MORC 2
HOW IT IS IMPLICATED IN DNA
DAMAGE RESPONSE. THE DIMERIZED
FORM GETS PHOSPHORYLATED BY THE
ATM DNA DOUBLE STRAND BREAK DNA
DAMAGE RESPONSE. IT SEEMS TO BE
NEEDED TO ASSIST DNA REPAIR.
ALSO SEEMS TO HAVE A ROLE IN
MORC 1 STABILITY AND INDICATED
IN DEPHOSPHORYLATION OF
PHOSPHORYLATED HISTONES. NOT A
GREAT DEAL WAS KNOWN ABOUT IT
AND HOW IT WORKED AND SEEMED A
FRUITFUL AREA FOR FURTHER
RESEARCH. SUMMARIZING THE
COCKAYNE SYNDROME CLINIC,
CURRENT CS PATIENTS CURRENTLY
VISITING A WIDE VARIETY OF
PHENOTYPE INCLUDING A
52-YEAR-OLD. UNFORTUNATELY
UNLIKE WITH XP NO CLEAR GENOTYPE
PHENOTYPE RELATIONSHIP IN THOSE
CASES. WE FOUND THIS OVER THE
YEARS WITH MANY COCKAYNE
PATIENTS AND IT IS CAUSE OF
FRUSTRATION TO US. WE FOUND THE
SEVERAL INTERESTING CASES OF CS
LIKE FEATURES WITH MUTATIONS IN
UNEXPECTED DNA REPAIR GENES. SO
HERE IS CS CLINICAL TEAM AGAIN
ON THEIR ANNUAL RETREAT TO
(INAUDIBLE) THIS WAS WAS JUST A
COUPLE OF WEEKS AGO. I THINK I
HAVE ACKNOWLEDGED ALL THE
PARTICIPANTS, ALL MY
COLLABORATORS, MY ROLE IN MUCH
OF WHAT I TALKED ABOUT HAVE BEEN
VERY MINIMAL BUT I THINK I WILL
LEAVE IT THERE AND TAKE ANY
QUESTIONS, THANK YOU VERY MUCH.
>> THANK YOU, PROFESSOR LEHMANN
FOR THE WONDERFUL TALK, IT IS
SUCH AN OVERVIEW FOR THE XP AND
FOR THE AUDIENCES PLEASE TYPE IN
YOUR QUESTION IN THE CHAT BOX.
AND THEN WE WILL ELABORATE OVER
HERE. WHILE OTHERS ARE TYPING IN
QUESTIONS, I HAVE A GENERAL
QUESTION OVER HERE. SO FOR THE
XP SEEMS LIKE THERE ARE VARIOUS
TYPE OF MUTATION. SO DO THEY
OFTEN COME WITH INHERITED
DISEASE OR LIKE SOMATIC DISEASE
LIKE (INAUDIBLE)?
>> BP ARE INHERITED, THE
MUTATIONS ARE INHERITED. THE
SOMATIC MUTATIONS GENERATED AS A
FUNCTION -- AS BY EXPOSURE TO UV
WHAT GENERATE THE (INAUDIBLE)
BUT THE INITIAL MUTATIONS ARE
INHERITED YES.
>> THANK YOU. I THINK DR. BOHR,
ARE YOU TALKING? YOU ARE ON
MUTE.
>> JUST A WONDERFUL TALK. THANK
YOU FOR THIS. ONE QUESTION I
HAD, IT IS REALLY INTERESTING
WITH THIS LOW LEVEL XPA BEING
SUFFICIENT TO AVOID
NEURODEGENERATION, IN THOSE
PATIENTS WAS IT THE LOWEST LEVEL
WAS 5% OR WAS IT AN AVERAGE 5%?
IS IT LIKE WE CAN SAY THAT
MINIMALLY 5% IS ENOUGH OR CAN WE
SAY AVERAGE 5% IS ENOUGH?
>> NO. OKAY. SO I THINK 5% OF --
I THINK WE CAN SAY THAT 5% OF
THE XPA PROTEIN IS ENOUGH. THE
LEVEL OF UVS I WOULD SAY IS NOT
-- WE DO A KIND OF QUICK AND
DIRTY UDS WHICH IS NOT
COMPLETELY QUANTITATIVE BUT FROM
THAT I WOULD SAY THE LEVEL OF
UDS WAS BETWEEN 5 AND 15% AND
THERE MAYBE SOME VARIABILITY
THERE.
>> REALLY INTERESTING. OKAY.
NOW, THERE'S SOME QUESTIONS IN
THE CHAT
>> SO (INAUDIBLE) SAID THANKS
FOR THE OUTSTANDING TALK AND
SHARING YOUR RECENT P 52 DATA.
SINCE DDB 2 KNOCKOUT MICE GET
INTERNAL TUMORS HAVE YOU SEEN
INTERNAL TUMORS IN XPE PATIENTS?
>> INTERNAL TUMORS, NO. THEY GET
-- I THINK KEN'S GROUP HAVE
REPORTED THIS AS WELL. BECAUSE
THEY ARE RELATIVELY MILD THEY
ARE NOT DIAGNOSED UNTIL LATE SO
BY THE TIME THEY ARE DIAGNOSED
THEY ACCUMULATED LOTS OF
MUTATIONS. SO LATER ON IN LIFE
30s, 40s AND 50s THEY GET
LOCKED IN SOMETIMES HUNDREDS OF
SKIN CANCER BUT WE HAVEN'T HAD
ANY INTERNAL TUMORS, PRETTY SURE
NO INTERNAL TUMORS.
>> YES. I WAS JUST TALKING
YESTERDAY WITH A XPE PATIENT IN
THEIR '60s. SHE DEVELOPED
THYROID CANCER. INTERESTINGLY
ENOUGH (INAUDIBLE) TAMORA HAD
HEARD ABOUT THYROID CANCERS IN
XP PATIENTS IN THE MIDDLE EAST
AND STARTED CALLING THE PATIENTS
AND ASKING THEM TO GET THYROID
ULTRA SOUNDS AND TURNED OUT SHE
HAD CANCER, IT WAS TOTALLY
UNSUSPECTED. SHE DID HAVE THAT.
BUT SIMILARLY SHE ALSO HAD
SEVERAL HUNDRED SKIN CANCERS.
ANOTHER COMMENT, WE PUBLISHED A
PAPER RECENTLY, IN THE LAB DID A
SURVEY OF THE LITERATURE AND THE
PATIENTS WE HAD -- WHO HAD
METASTATIC CANCER WITH XP AND
THEY WERE TREATED WITH IMMUNE
CHECK POINT INHERES TO. . BEHAD
SEVERAL DOZEN AND THEY ALL
RESPONDED VERY WELL.
INDEPENDENT OF THE PARTICULAR
MUTATIONS IN THEIR TUMORS.
>> (INAUDIBLE) THOSE WERE
SECs?
>> A VARIETY OF DIFFERENT ONES.
>> OKAY.
>> HERE IS A QUESTION FROM
DMITRI. YOU MENTIONED MELANOMA
IN XP POSITIVE INDIVIDUAL HAS
HUNDREDS OF THOUSANDS OF
AMYATIONS IN UV LIGHT MOTIF.
WHAT IS THE CURRENT FEUD WITH
ALL THE ORIGIN OF SUCH
HYPERMUTATION?
>> I GUESS THAT IS WHAT YOU
PREDICT. BECAUSE NER OR XP
VARIANTS TLS IS DEFECTIVE,
SHOWED EARLY VERONICA'S GROUP
SHOWING HYPERMUTABILITY SO I
THINK THAT IS EXACTLY WHAT YOU
WOULD PREDICT FROM AN XP
INDIVIDUINDIVIDUAL. THAT SHE WOE
LOTS OF MUTATIONS.
>> CAN I ASK QUICKLY, THE MORC 2
MUTATION ONLY SEEN IN CS LIKE
CONDITIONS OR OTHER DNA REPAIR
DISEASES?
>> SEEN IN OTHER DISEASES BUT
NOT OTHER DNA REPAIR DISEASES.
>> OKAY. WHAT DISEASES IS IT
SEEN IN?
>> I THINK IT IS --
>> TS 1 --
>> (INAUDIBLE) 2 DISEASE.
>> YES.
>> IF YOU CHECK OUT THAT REVIEW
YOU CAN GET ALL THE INFORMATION
ON THE (INAUDIBLE) 2022. IT IS
THE MUTATIONS SEEM TO BE DE NOVO
MUTATIONS IS DOMINANT MUTATION.
>> DMITRI HAS A FOLLOW-UP POINT
SAYING HIS QUESTION IS ABOUT XP
WILD TYPE PATIENTS.
>> SORRY --
>> I THINK HE'S TALKING
MELANOMAS IN IN INDIVIDUAL WHOSE
ARE WILD TYPE FOR XP.
>> OKAY. SO THE QUESTION IS, THE
POINT IS THEY'RE VERY HIGH
LEVELS OF MUTATIONS, (INAUDIBLE)
IS CERTAINLY THE QUESTION?
>> HIS QUESTION IS PROBABLY XP
WILD TYPE MELANOMA INDIVIDUAL
HAVE HUNDREDS OF CELLS IN UV
LIGHT MOTIF. SO WHAT IS THE VIEW
ON THE ON ORIGIN OF SUCH
HYPERMUTATION LOAD?
>> SORRY I MISUNDERSTOOD. WE ARE
TALKING NORMAL INDIVIDUALS HAVE
-- WHO HAVE VERY HIGH LEVELS OF
MUTATIONS IN THEIR MELANOMA, I
GUESS THAT IS THE QUESTION. NOT
SURE I CAN GIVE A SENSIBLE
ANSWER TO THAT. SORRY. I DON'T
KNOW IF KEN OR ANYONE ELSE CAN
--
>> IT IS AN ARGUMENT THAN LINKS
MELANOMAS TO UV EXPOSURE.
>> I LIKE TO POINT OUT
(INAUDIBLE) ATTENDING THIS
LECTURE TODAY H.
>> GREAT.
>> ALSO THE YOU MENTION XP AND
COCKAYNE WITH MUSCULAR DYSTRO
DYSTROPHY, WE HAVE SEEN
MUTATIONS WITH XP AND
(INAUDIBLE) IN COCKAYNE
SYNDROME, IT GETS TRICKY
CLINICALLY DISTINGUISHING AMONG
THETHEM.
>> WE HAVE WORKING ON THAT FOR
YEARS.
>> YES.
>> THERE IS ANOTHER QUESTION IN
THE CHAT. FROM (INAUDIBLE). MANY
XP PATIENTS BENEFIT FROM ICB
THERAPY, IS THIS THE TIME TO
DEVELOP AN INTERNATIONAL
CLINICAL GUIDELINE BASED ON
PRIOR RESULTS?
>> SORRY I DON'T KNOW WHAT ICB
IS. CAN --
>> IMMUNE CHECK POINT BLOCKADE.
>> OKAY. SORRY. YES. SURE. ANY
INTERNATIONAL COLLABORATION WITH
PATIENTS WOULD BE VERY USEFUL.
>> LAST CHANCE FOR PEOPLE TO PUT
QUESTIONS IN THE CHAT. OKAY. WE
HAVE SOME QUESTION FROM
(INAUDIBLE). THANKS FOR THIS
NICE TALK. WHILE ANALYZING DATA
FOR ATYPICAL FORM OF XP PATIENTS
I FIND VARIANTS IN GENES RELATED
TO NER BUT NOT THE KNOWN GENES
BEING SO FAR REPORTED FOR XP.
BUT I'M HESITATING BEFORE
PUBLICATION. SO THANK YOU
BECAUSE WITH THIS NEW GROUP WE
CAN NOW EXPECT NEW GENES IN THE
NER PATH BAY, EVEN OTHER
PATHWAYS RELATED TO DNA REPAIR.
MY QUESTION IS TO WHAT EXTENT
CAN WE BE CONFIDENT IN REPORTING
NEW GENES ESPECIALLY WHEN THE
ONLY PROOF I HAVE IS IN SILICO
FINDINGS?
>> SO THERE IS A PROBLEM THEN
YOU CAN ONLY BE REALLY CONFIDENT
IF YOU HAVE CELLS SHOW THERE IS
A CELLULAR DEFECT IN THE
RESPONSE TO UV AND THAT CAN BE
CORRECTED BY THE GENE YOU
IDENTIFIED, CDNA AND ALTHOUGH IF
I'M CORRECT I THINK YOU ARE IN
MOROCCO AND YOU HAVE FACILITIES
THERE, SURE YOU CAN FIND
COLLABORATORS WHO WOULD BE
PLEASED TO DO THOSE KINDS OF
EXPERIMENTS. IF YOU ARE NOT THE
PERSON I THINK YOU ARE.
>> IT SAYS NO OPPORTUNITIES YET.
>> SORRY.
>> I THINK WE DON'T SEE ANY
ADDITIONAL QUESTIONS. WITH THE
LIMITATION OF TIME WE WILL
PROBABLY JUST WRAP UP HERE AND
PLEASE JOIN ME IN THANKING DR.
LEHMANN AGAIN FOR THE WONDERFUL
OVERVIEW OF THE XP. THANK YOU,
EVERYBODY FOR THE PARTICIPATION.
IN JANUARY WE WILL HAVE OUR
VIDEO CONFERENCE CONTINUE WITH
ANDREA NUSSENSWAG AND FELLOW TO
PRESENT RECENT FINDINGS. THANK
YOU. SEE YOU NEXT TIME.
>> THANK YOU.
>> THANKS, ALAN.
>> WONDERFUL TALK.