Mendelian Inheritance

Question 1

Huntington’s Disease

Answer 1

Autosomal dominant
(occurs at every generation)

Question 2

Sickle Cell Disease

Answer 2

Autosomal recessive

rare; more probable in matings of relatives

Question 3

Red/Green Colour Blindness

Answer 3

X linked recessive

predominantly in males

Question 4

Rett Syndorome

Answer 4

X linked dominant

every generation; affected males always pass to daughters but never to sons

Question 5

Male affected only

Answer 5

Y linked

Question 6

Cystic Fibrosis

Answer 6

Autosomal recessive

Question 7

Retinoblastoma

Answer 7

Autosomal dominant (also non-heritable)
Rb TSG
Bilateral manifestation

Question 8

Breast cancer

Answer 8

Autosomal dominant

BRCA 1/2 TSG

Question 9

HNPCC

Answer 9

Autosomal dominant
MLH1 mutation (DNA repair)
No polyps

Question 10

FAP

Answer 10

Autosomal dominant
APC TSG mutations
Severe colonic polyposis
CHRPE may be present

Question 11

AFAP

Answer 11

Autosomal dominant
APC TSG mutations
Mild colonic polyposis
No CHRPE

Question 12

MAP

Answer 12

Autosomal recesive
MYH gene (DNA repair)
Varying degrees of colonic polyposis