Syndromes

Question 1

Fragile X inheritence

Answer 1

X-linked dominant - so also affects carrier girls

Question 2

X linked chromosomal abnormality

Answer 2

Allelic expansion causes fragility
Increase in repeats in successive generations til it’s sympomatic

Question 3

Clinical features of fragile X

Answer 3

Learning difficulties
Anxiety
ADHD

Question 4

Rett syndrome: presentation

Answer 4

Always girls
Normal early developement, walk and talk
Regression - lose those skills
Hand movements - wringing

Question 5

Rett syndrome: cause

Answer 5

Mutations of MECP2 gene
99% spontaneous mutations

Question 6

Bloom syndroe: clinical features

Answer 6

Photosensitivity
Telangiectatic erythema of face
Stunted growth
(Recurrent infections, malignancies)

Question 7

Bloom syndrome: cause and inheritence

Answer 7

Autosomal recessive
Defect in DNA repair system

Question 8

MCADD cause

Answer 8

Fatty acid oxidation defect
Medium chain acyl-CoA dehydrogenase deficiency

Question 9

MCADD presentation

Answer 9

Hypoketotic hypoglycaemia after a period of fasting - interupts pathways that produce ketones

Question 10

Glutaric aciduria type 1: presentation

Answer 10

Macrocephaly + hypoteonia
Developmentally delayed
Acute encephelopathic crisis: CT findings of bilateral subdural haemorrhage

Question 11

Physical features fragile X

Answer 11

Long narrow face
Prominent jaw + forehead
Big ears