Genetic associations and modes of inheritance

Question 1

Down’s Syndrome

Answer 1

Trisomy 21

Question 2

Cystic Fibrosis - What gene and chromosome? How is it inherited?

Answer 2

CFTR gene on chromosome 7

Autosomal recessive

Question 3

Seronegative arthropathies

Answer 3

HLA B27

Question 4

Type 1 diabetes

Answer 4

HLA DQ8

Question 5

Philadelphia chromosome - What disease is it associated with? What is the translocation? Name the fusion gene that is formed

Answer 5

Chronic myeloid leukaemia

t(9;22)

BCR-ABL

Question 6

Acute myeloid leukaemia - give a translocation and an associated disease

Answer 6

t(15;17)
Down’s syndrome

Question 7

Acute lymphoblastic leukaemia - give a translocation and an associated disease

Answer 7

t(12;21)

Question 8

Polycythaemia vera

Answer 8

JAK2V617

Question 9

Haemophilia

Answer 9

X-linked deficiency of factor VIII (type A) or IX (type B)

Question 10

Breast cancer

Answer 10

BRCA1 and BRCA 2

Question 11

There are 2 inherited mutations which can increase risk of bowel cancer - Name them

Answer 11

Lynch syndrome or Hereditary Non Polyposis Colorectal Cancer (HNPCC)

Familial Adenomatous Polyposis

Question 12

Duchenne Muscular Dystrophy

Answer 12

X-linked inheritance

Question 13

Neural tube defect

Answer 13

Multifactorial

Question 14

Name a disease with mitochondrial inheritance

Answer 14

Leber’s hereditary optic neuropathy (LHON)

Question 15

2 diseases are caused by the same mutation. What are these diseases? Where is the mutation? What determines which phenotype is expressed? What is the name of this phenomenon?

Answer 15

Angelmans syndrome and Prader-Willi
Deletion of a region of chromosome 15
Deletion of paternal gene = Prader Willi
Deletion of maternal gene = Angelmans
Genomic imprinting

Question 16

Variable penetrance

Answer 16

% of individuals carrying a genetic variant who manifest a disease

Question 17

Age related penetrance

Answer 17

% of individuals who develop a given genetic disease at different ages

Question 18

Variable expressivity

Answer 18

Different phenotypes expressed by different people with the same genetic disease

Question 19

Huntington’s disease

Answer 19

Autosomal dominant

Question 20

Alpha thalassemia

Answer 20

4 gene deletions on chromosome 16 - Number of deletions affects severity of presentation

Question 21

Beta thalassemia

Answer 21

2 gene mutations on chromosome 11 - Number of mutations affected severity of presentation

Question 22

Sickle cell anaemia

Answer 22

Autosomal recessive

Question 23

G6PDH deficiency

Answer 23

X-linked

Question 24

Hereditary spherocytosis

Answer 24

Autosomal dominant

Question 25

Coeliac disease

Answer 25

HLA DQ2 and DQ8

Question 26

Osteoarthritis

Answer 26

COL2A1

Question 27

Rheumatoid arthritis

Answer 27

HLA DR4
HLA DRB1

Question 28

Systemic lupus erythematosus

Answer 28

HLA B8/DR2/DR3

Question 29

Polymyositis / dermatomyositis

Answer 29

HLA B8/DR3

Question 30

Marfan’s - give mode of inheritance and the mutation

Answer 30

FB1 mutation
Auto dom

Question 31

Ehlers Danlos

Answer 31

Auto dom