Genetics introduction

Question 1

What is variable expression?

Answer 1

The same faulty gene causing different effects/ clinical presentaiton

Question 2

What is incomplete penetrance?

Answer 2

If a mutation (pathogenic variant) does not always cause disease in every person then it is incomplete

Question 3

What is complete penetrance?

Answer 3

When a gene (pathogenic variant) causes disease in every person that inherits it

Question 4

What is the ‘knights move’ a feature of?

Answer 4

x linked recessive inheritance

Question 5

What is genetic anticipation?

Answer 5

An increase in the number of trinucleotide repeats in a gene. There is increasing severity and earlier age of onset in successive generations

Question 6

Describe mitochondrial inheritance

Answer 6

Inherited from the mother, all children inherited it but to variable extents. The syndromes often affect the muscle, brain and eyes

Question 7

What is the inheritance pattern of APKD?

Answer 7

Autosomal dominant (adult polycystic kidney disease)

Question 8

What is the inheritance pattern of neurofibromatosis type 1?

Answer 8

Autosomal dominant

Question 9

What is the inheritance pattern of Huntington disease?

Answer 9

Autosomal dominant

Question 10

What is the inheritance pattern of cystic fibrosis?

Answer 10

Autosomal recessive

Question 11

What is the inheritance pattern of phenylketonuria?

Answer 11

Autosomal recessive

Question 12

What is the inheritance pattern of Spinal muscular atrophy?

Answer 12

Autosomal recessive

Question 13

What is the inheritance pattern of Wilson disease?

Answer 13

Autosomal recessive

Question 14

What is the inheritance pattern of Tay-sachs disease?

Answer 14

Autosomal recessive

Question 15

What is the inheritance pattern of Vitamin D resistant rickets?

Answer 15

X linked dominant

Question 16

What is the inheritance pattern of incontinentia pigment

Answer 16

x linked dominant

Question 17

What is the inheritance pattern of Rett syndrome?

Answer 17

x linked dominant

Question 18

What is the inheritance pattern of haemophilia B?

Answer 18

x linked

Question 19

What is the inheritance pattern of duschen muscular dystrophy?

Answer 19

x linked

Question 20

What is the inheritance pattern of achondroplasia?

Answer 20

Autosomal dominant

Question 21

What is the inheritance pattern of haemophilia A?

Answer 21

x linked

Question 22

What is the inheritance pattern of MERRF?

Answer 22

mitochondrial

Question 23

What is the inheritance pattern of MUTYH-associated polyposis?

Answer 23

Autosomal recessive

Question 24

What is the inheritance pattern of haemochromatosis?

Answer 24

Autosomal recessive

Question 25

What is the inheritance pattern of Lynch syndrome?

Answer 25

Autosomal dominant

Question 26

What is the inheritance pattern of Marfan syndrome?

Answer 26

Autosomal dominant

Question 27

What is the inheritance pattern of MELAS?

Answer 27

mitochondrial