Infertility

Question 1

% of male infertility with genetic factor

Answer 1

15% (25% in azoospermia)

Question 2

4 causes of male infertility

Answer 2

Sperm quantitative defects

Ductal obstruction

Hormone disturbance

Sperm qualitative defects

Question 3

% female infertility with genetic factor

Answer 3

10%

Question 4

3 mechanisms of chr rearrangement formation

Answer 4

NHEJ

NAHR

Centric fusion

Question 5

mechanism for t(11;22)(q23;11)

Answer 5

NHEJ between PATRR regions susceptible to DNA breaks

Question 6

mechanism for t(4;8)(p16;p23)

Answer 6

NAHR between homologous OR gene clusters

Question 7

Incidence of robertsonian translocations

Answer 7

1.1% of recurrent miscarriage couples

3% of infertile males

Question 8

How are chr rearrangements linked to infertility?

Answer 8

Failure of synapsis in prophase 1 of meiosis

Activation of meiotic pachytene checkpoint

Cell death of gametes

Question 9

Why are male carriers of balanced rearrangements more likely to be infertile?

Answer 9

Oocytes can bypass checkpoints

Sperm cells are more vulnerable to checkpoint and cell death