Patterns of Inheritance

Question 1

When an allele of a gene produces several phenotypic effects

Answer 1

Pleiotropy

Question 2

The probability that gene will have any phenotypic expression at all

Answer 2

Penetrance

Question 3

The severity of expression of the phenotype

Answer 3

Expressivity

Question 4

Renal cysts diagnosable by ultrasound, leads to progressive renal failure, extrarenal problems including cysts in liver or pancreas, cerebral aneurysm, mitral valve prolapse (autosomal dominant)

Answer 4

Polycystic kidney disease (ADPKD)

Question 5

Polycystic kidney disease is caused by a defect in the _____ gene 95% of the time and _____ 5% of the time

Answer 5

PKD1 and PKD2

Question 6

Inborn errors of metabolism typically have what type of inheritance

Answer 6

autosomal recessive

Question 7

Autosomal recessive. Severe mental and physical deterioration, develop normally for first few months of life but then deterioration and death occur by 2-3 yo due to accumulation of ganglioside GM2 in neurons. Cherry red spot on retina

Answer 7

Tay-Sachs Disease

Question 8

Autosomal recessive. Mental retardation, fair skin, eczema, epilepsy, preventable if prompt dietary treatment given. Mutations in liver enzyme phenylalanine hydroxylase.

Answer 8

Phenylketonuria

Question 9

% of genes shared between first degree relatives

Answer 9

50%

Question 10

% of genes shared between second degree relatives

Answer 10

25%

Question 11

% of genes shared between third degree relatives

Answer 11

12.5%

Question 12

% of genes shared between fourth degree relatives

Answer 12

6.25%

Question 13

Marriage between persons with the same surname

Answer 13

Isonymous marriage

Question 14

X-linked recessive. Coagulation disorder characterized by the inability of blood to clot, leading to hemorrhaging into joints and muscles, even from minor injuries

Answer 14

Hemophilia A

Question 15

X-linked recessive. Progressive muscle weakness, pseudohypertrophy of calf muscles, onset in early childhood, death by 30s.

Answer 15

Duchenne Muscular Dystrophy

Question 16

X-linked dominant. Rare mental retardation syndrome in females, usually lethal in males. Defect in methyl-CpG-binding protein9. Normal initial development followed by rapid decline in progression plus onset of ataxia (inability to coordinate muscle activity during voluntary movements) and dementia

Answer 16

Rett Syndrome

Question 17

X-linked dominant. Ability of kidney to reabsorb phosphate is reduced leading to hypophosphatemia

Answer 17

Hypophosphatemic rickets / Vitamin D-resistant rickets

Question 18

Mitochondrial. Rapid, bilateral loss of central vision due to optic nerve death in young adults.

Answer 18

Leber’s Hereditary Optic Neuropathy (LHON)

Question 19

Mitochondrial. External opthalmoplegia (paralysis of eye). Pigmentary degeneration of the retina and cardiomyopathy

Answer 19

Kearns-Sayre Syndrome (KSS)

Question 20

Myoclonic epdepsy and ragged red fiber disease has what type of inheritance

Answer 20

Mitochondrial

Question 21

Pertains to set of genes carried by both the X and Y chromosomes. These genes are involved with disorder known as sex reversal.

Answer 21

Pseudoautosomal inheritance

Question 22

Probability of either of two mutually events occurring. What do you do?

Answer 22

Probability is the sum of their individual probabilities. Additivity principle.

Question 23

Probability of two or more independent events occurring together. What do you do?

Answer 23

Probability is the product of their individual probabilities. Independence principle.

Question 24

In the binomial equation, which term designates the probability of a single affected child.

Answer 24

A

Question 25

In the binomial equation, which term designates the probability of a single normal child.

Answer 25

B

Question 26

In the binomial equation, which term designates the number of children

Answer 26

n

Question 27

Five drivers which deviate from the Hardy-Weinburg conditions

Answer 27

1) mutation
2) gene flow (migration of individuals in or out)
3) selective mating
4) genetic drift
5) selection