Genodermatoses

Question 1

what are the three major groups of genodermatoses

Answer 1

ichthyoses, epidermolysis bullosa, tumor syndromes

Question 2

epidermolytic ichthyosis: where are mutations? How does it often present

Answer 2

kertatin 1 or 10. Mosaic pattern along Blaschko’s lines of embryonic development

Question 3

lamellar ichthyosis: deficiency of what?

Answer 3

transglutaminase 1

Question 4

CHILD syndrome: inheritance, acronym, deficiency, tx

Answer 4

X-linked dominant (only girls survive). congenital hemidysplasia with ichthyosis and limb defects. deficiency of cholesterol synthesis enzymes. give statin and cholesterol

Question 5

three types of epidermolysis bullosa and where?

Answer 5

simplex, junctional, dystrophic (below BM) (dominant and recessive)

Question 6

mutation leading to EB simplex

Answer 6

keratin 5 or 14, cleavage through stratum basale

Question 7

where are the mutations in JEB

Answer 7

hemidesmosome.

Question 8

DDEB vs RDEB: description, mutation, inheritance

Answer 8

DDEB is blistering and milia, dominant neg in col 7. RDEB is itching, fragility, fusion of digits Autosomal recessive chain termination COLVII

Question 9

Neurofibromatosis: inheritance, markers, features

Answer 9

AD, cafe au lei and lisch nodules (eye), neural tumors

Question 10

tuberous sclerosis: inheritance, markers, features

Answer 10

AD, white spots on neonates, seizures and retardation along with benign skin tumors.

Question 11

Genetic heterogeneity: define, example

Answer 11

different genes, same manifestations. Tuberous sclerosis can result from hamartin or tuberin genes

Question 12

Basal cell nevus syndrome: mutation, problems

Answer 12

PTCH which keeps SHH in check. Medulloblastomas in kids, BCC in adults

Question 13

tx of tuberous sclerosis

Answer 13

rapamycin blocks mTOP signaling