1. GROUP 4

2. XERODERMA
PIGMENTOSUM

3. INTRODUCTION

4. Xeroderma pigmentosum, or XP,
is an autosomal recessive genetic disorder of DNA repair
in which the ability
to repair damage caused by
ultraviolet (UV) light
is deficient.

5. NORMAL CONDITION without XP

6. Exposure to UV light Thymine dimer No replicating DNA strand
DNA DAMAGES
Exposure to UV light
Thymine dimer
No replicating DNA
strand

7. Nucleotide excision repair
REPAIR SYSTEM
Nucleotide excision repair
Recognization
Unwinding
Cleavage
Filling
Sealing

8. ABNORMAL

9. NUCLEOTIDE EXCISION REPAIR
Uvr-ABC excinuclease
DNA Polymerase
DNA Ligase
skin
GENE

10. SKIN UV The POL H gene (encoded DNA polymerase eta (Pol η))
Xeroderma pigmentosum
protecting cells from UV thatinduced DNA damage
fix DNA damage

11. Type of XP & inherited mutation gene
Type A, I, XPA
Type E, V, XPE
Type B, II, XPB
Type F, VI, XPF
Type of XP & inherited mutation gene
Type C, III, XPC
Type G, VII, XPG
Type D, IV, XPD
Type V, XPV

12. autosomal recessive genetic disorder of DNA repair

13. Signs and Symptoms of Xeroderma Pigmentosum

14. Severe sunburn when exposed to small amounts of sunlight
Severe sunburn when exposed to small amounts of sunlight. These often occur during a child's first exposure to sunlight.
Development of many freckles at an early age
 Skin Cancer
Eyes that are painfully sensitive to the sun and may easily become irritated and bloodshot

15. Blistering on minimum sun exposure
 Spidery blood vessels
Scaly and dry skin
Irregular dark spots on the skin

16. Bloodshot
freckles
blister
blister
Scaly skin

17. DIAGNOSIS Usually detected in early infancy 1-2 years
Clue to diagnosis - severe sunburn after first exposure to the sunlight
The diagnosis of XP is made on the basis of clinical findings and family history
The diagnosis of XP is based on skin, eye, and nervous system
XP can be diagnosed by measuring the DNA repair factor from skin or blood sample

18. Prompt removal of cancerous tissueB L E
Treatment For XP
Protection from UV
Eye and skin exam
Prompt removal of cancerous tissue
Neurological exam
Psychososial care

19. PrOGNOsi$
*Many patients die at an early age from skin cancers.but,if a person is diagnosed early, does not have severe neurological symptoms and takes all the precautionary measures to avoid exposure to UV light, they may survive beyond middle age.
< 40% of individuals with the disease survive beyond age 20. Some with less severe cases manage to live well into their 40s

20. CONCLUSION

21. THANK YOU