Genetics

Question 1

Peutz-Jegher’s syndrome

Chromosome

Features + presentation

Answer 1

Chromosome 19, AD

Pigmented buccal lesions and GI polyps

Presents often w obstruction due to intussusception, or abdominal pain, haematochezia, prolapsed polyp

Question 2

Cystic fibrosis mutation

Answer 2

Cystic fibrosis transmembrane conductance regulator gene (AR inheritance)

In the UK 80% of CF cases are due to delta F508 on the long arm of chromosome 7.

Question 3

Ankylosing spondylitis - mutation, sex

Answer 3

HLA-B27 90-95% of cases
Men 3:1

Question 4

Ankylosing spondylitis
Extra-spinal 6 A’s

Answer 4

AVN block
Aortic regurgitation
Amyloidosis
Anterior uveitis
Apical fibrosis
Achilles tendonitis

Question 5

Huntington’s disease
Chromosome, inheritance

Answer 5

Chromosome 4
AD
Trinucleotide repeat disorder

Question 6

Huntingtons presentation

Answer 6

Usually after age 35
Chorea
Personality change, mood disorder
Saccadic eye movement
Dystonia

Question 7

HOCM genetics

Answer 7

AD
contractile protein gene disorder

Question 8

Fragile X

Answer 8

X-linked dominant, variable penetrance
Commonest inherited cause of general learning disability

Question 9

Osler-Weber-Rendu Syndrome AKA
Characterised by

Answer 9

Hereditary haemorrhagic telangiectasia

Autosomal dominant

Frequent epistaxis, telangiectasia, positive family history