Y-chromosome microdeletions (del Y)

Microdeletions of the Y chromosome may occur in men with infertility problems, such as azoospermia (complete absence of sperm cells), severe oligozoospermia (<1 x 106 sperm cells/ml of semen) or mild oligozoospermia. Males with infertility due to Y-chromosome microdeletions usually have no visible symptoms, although physical examination may reveal small testicles and/or cryptorchidism. Due to the fact that men presenting with a microdeletion in one of the AZF regions (azoospermia factor) of the long arm of the Y chromosome are practically infertile, it is concluded that these microdeletions typically occur de novo.

We perform a specially designed multiplex PCR assay for the analysis of specific STS markers spanning the entire AZF region, as recommended by the European Academy of Andrology (EAA). The number and morphology of sperm cells should be evaluated in parallel.

The test is indicated in male patients with reproductive problems and is particularly useful in the evaluation of cases undergoing routine IVF/ ICSI as well as for determining the risk of transmitting the abnormality to male progeny.

NOTE: Our laboratory participates with great success in the external quality assessment scheme organized by the European Molecular Genetics Quality Network (EMQN) – EAA, which is periodically applied for Y-chromosome microdeletion testing.

This test may also be applied in combination with:

  • Peripheral blood karyotype test
  • Molecular genetic testing for cystic fibrosis, which includes reflex testing for the 5T,7T and 9T polymorphic variants along with certain CFTR mutations known to lead to CBAVD.