Genetics in MRCP

Today I am going to tell you a few genetics conditions which are commonly asked in your MRCP PART 1.

1) Autosomal dominant inheritance
- generally ‘ structural-type’ disorders

a) adult polycystic kidney disease
b) myotonic dystrophy
c) Elers-Danlos and Marfan’s syndrome
d) Hereditary haemorrhagic telangiectasia
e) Huntingtons chorea
f) Intestinal polyposis
g) Neurofibromatosis
h) Otesogenesis imperfecta
i) Tuberous sclerosis

2) Autosomal Recessive inheritance
- generally ‘metabolic type’ disorders

a) Infantile polycystic kidney
b) Alfa1-antitrpsin deficiency
c) Cystic fibrosis
d) Most inborn errors of metabolism ( galactosaemia, glycogen storage diseases etc)
e) Haemoglonbinopathies ( sickle cell disease and thalassaemias)
f) Wilson’s disease
g) Friedreich’s ataxia

3) Sex-linked dominant inheritance

a) Vitamin D risistnact rickets

4) Sex-linked recessive inheritance

a) G6PD deficiency
b) Haemophilia A and B
c) Lesch-Nyhan syndrome
d) Immunodeficinecies- agammagobulinaemia

However, there are a few types of muscular dystrophies you should remember,

Duchenne - X linked recessive
Becker -X linked recessive
Limb girdle -Autosomal recessive
Facio-scapulo-humerol -Autosomal dominant

Tips for MRCP

Remember how to interpret a family tree, it is the commonest way how genetics of above disoredrs are asked in MRCP!