Types of Y chromosome microdeletions

Microdeletions in the Y chromosome are losses of chromosomal material that can lead to fertility problems in the male. However, depending on the area where the microdeletion occurs, the impact may be different:

• AZFa: more related to Sertoli syndrome alone and, therefore, to azoospermic males.
• AZFb or AZFb/c: associated with a maturational arrest in the process of spermatogenesis and, thus, with the absence of spermatozoa in their final form.
• AZFc: in this case, the male may present oligospermia or azoospermia.

Microdeletions in AZFc are the most common, but they are the ones with the best reproductive prognosis since it is quite possible to recover spermatozoa by testicular biopsy or even in the ejaculate.