Genetic Syndromes

Question 1

Which gene is mutated in Loeys Dietz Syndrome?

Answer 1

TGFbeta-receptors 1 and 2

Question 2

Familial Thoracic Aortic Aneurysm and Aortic Dissection (TAAD) Syndrome
- ? autosomal status

Answer 2

Autosomal dominant

Question 3

SMAD3 mutation

Answer 3

• Thoracic Ao aneurysm
• Craniofacial and skeletal abnormalities
• Osteoarthritis

Question 4

Kearns-Sayre-Syndrome features?

Answer 4

Ophthalmoplegia
Cardiomyopathy
Sinus bradycardia
Retinal depigmentation

Question 5

Prader Willi Syndrome

- inheritance

Answer 5

Paternal imprinting of Ch15

Question 6

Laurence Moon Syndrome

- inheritance

Answer 6

Autosomal recessive

Question 7

Laurence Moon Syndrome

- features

Answer 7

Obesity
Hypogonadism
Mental retardation
Polydactyly
Retinitis Pigmentosis

Question 8

Inheritance of Androgen Insensitivity Syndrome?

Answer 8

X-linked recessive condition due to end-organ resistance to testosterone causing genotypically male children (46XY) to have a female phenotype

Complete androgen insensitivity = testicular feminisation syndrome

Question 9

Features of Androgen Insensitivity Syndrome

Answer 9

Primary amenorrhoea

Undescended testes causing groin swellings

Breast development may occur due to conversion of testosterone to oestradiol

Question 10

Diagnosis of Androgen Insensitivity Syndrome

Answer 10

High LH
Normal/High Testosterone

Chromosome analysis for 46XY genotype

Question 11

Management of androgen insensitivity syndrome

Answer 11

Counselling

Bilateral orchidectomy (increased risk of testicular cancer due to undescended testes)

Oestrogen therapy