Pedigree Analysis, Applications and Genetic Testing

Question 1

Constraining features of genetic study in humans

Answer 1

Controlled mating is not possible
Long generation time
Small family size

Question 2

Pedigree

Answer 2

A family tree that outlines the inheritance of one or more characteristics

Question 3

Proband

Answer 3

The person from whom the pedigree is initiated

Question 4

Characteristics of autosomal recessive traits

Answer 4

appear equally in males and females
Tend to skip generations
More likely to appear among progeny of related parents

Question 5

Characteristics of autosomal dominant traits

Answer 5

Appear equally in males and females
Unaffected persons do not transmit the trait
Affected persons have at least one affected parent

Question 6

Characteristics of X-linked recessive traits

Answer 6

Affected males do not transmit the trait to their sons
But can pass it to their daughters, who is unaffected
Daughters of affected males pass the trait on to their sons.
Appear more frequently in males.

Question 7

Characteristics of X-linked dominant traits

Answer 7

Do not skip generations
Affected males pass the trait on to all of their daughters and none of their sons
Affected females (if heterozygous) pass the trait on to half of their sons and half of their daughters

Question 8

Characteristics of Y-linked traits

Answer 8

Appear only in males

All male offspring of an affected male are affected

Question 9

Concordant trait

Answer 9

The trait shared by both members of a twin pair

Question 10

Amniocentesis

Answer 10

Performed at 15th to 18th week of pregnancy

Question 11

Chorionic Villus Sampling (CVS)

Answer 11

Performed at 10th to 12th week of pregnancy