Module 13

Question 1

Which (one) of the following diseases is/are correctly classified as autosomal dominant?

Answer 1

Huntington and achondroplasia

Question 2

Which (one) of the following modes of inheritance is/are compatible with the following statement?

An affected male and an affected female produce both affected and unaffected male and female children.

Answer 2

Autosomal dominant

Question 3

Males are hemizygous for X-linked traits

Answer 3

True

Question 4

What one word term is used in reference to the person that acts as a starting point for pedigree analysis, typically because they are affected by a genetic disease?

Answer 4

Proband

Question 5

A mother is heterozygous for an X-linked recessive disease allele and she has children with a phenotypically-normal male. What proportion of the FEMALE children would be expected to show the disease phenotype?

Answer 5

0%

Question 6

A father is heterozygous for an autosomal dominant disease. He has children with a female that is heterozygous for the same gene. What percentage of the children would be expected to be affected (i.e. show the disease phenotype)?

Answer 6

75%

Question 7

Consider the case of X-linked dominant inheritance. What is/are possible genotypes of an affected female?

Answer 7

XAXa and XAXA

Question 8

Affected

Answer 8

any person having a given disorder

Question 9

Heterozygote

Answer 9

person possessing one copy of the mutated gene coding for a disorder.

Question 10

Homozygote

Answer 10

person possessing two copies of the allele for a disorder

Question 11

Carrier

Answer 11

Unaffected heterozygote

Question 12

Autosomal dominant traits

Answer 12

affected children born to affected parent
both males and females equally
neither parent is affected, usually child isn’t either
does not skip generations

Question 13

Autosomal dominant disorders

Answer 13

Achondroplasia, Huningtons, Marfans, Polydactyly

Question 14

Autosomal recessive traits

Answer 14

Affected children born to unaffected parents
both male and female affected equally
children born to parents with common ancestry
skips one or more generations

Question 15

Autosomal recessive disorders

Answer 15

Cystic fibrosis

Question 16

X-linked recessive traits

Answer 16

Affected sons born to unaffected mothers
far more males affected
the trait never passes from father to son
disorder skips one or more generations

Question 17

X-linked dominant traits

Answer 17

Affected mothers have both affected sons and daughters
both males and females effected
all daughters of affected fathers are affected
doesn’t skip generations

Question 18

Y-linked traits

Answer 18

Affected men pass the traits onto sons
No women
the trait does not skip generations