Y 染色體微基因刪除遺傳測試

What is azoospermia?

Azoospermia is a condition in which the affected man has no sperms in his ejaculate, so that he is unable to father children. Obstructive azoospermia can be corrected by surgery, or sperms can be extracted from testes for intracytoplasmic sperm injection (ICSI). In contrast, non-obstructive azoospermia is characterized by lack of production or maturation arrest of sperms (Sertoli cell-only syndrome). Since there are no mature sperms in the testes, sperm extraction and ICSI should not be recommended to men having such condition.

What causes non-obstructive azoospermia?

Microdeletions of regions called azoospermia factor (AZF) a, b, and c on the Y chromosome are detectable in approximately 10% of men with azoospermia and severe oligospermia (smaller number of sperms than usual). Complete deletions of AZFa, AZFb or AZFb+c result in azoospermia, while deletions of AZFc are found in men with azoospermia or severe oligospermia.

Can microdeletions of Y chromosome be inherited?

Since men with non-obstructive azoospermia cannot father children, this condition is usually caused by new deletions on the Y chromosome and occurs in men with no history of the disorder in their family. Men with AZFc deletions and severe oligospermia may father children, either naturally or with the aid of ICSI, and pass on the microdeletions to all their sons.

What is this test for?

This test detects microdeletions of the three regions AZFa, AZFb and AZFc on the Y chromosome that are associated with azoospermia and oligospermia.

Who should consider this test?

  • Recurrent unsuccessful fertilization


3 mL blood in EDTA tube (kept at 4°C)
5 日

Rejection criteria

  • Specimen without proper labeling
  • Specimen not in requested format or insufficient quantity
  • Specimen in container expired for more than 1 month
  • Container leakage
  • Sampling date is more than 7 days
  • Frozen, haemolysed or clotted blood specimen 

Factor(s) known to affect results

  • Improper collection, handling and storage of specimen