Description
The Y Chromosome Microdeletion Test is a highly specialized genetic blood test used to evaluate severe male infertility. It looks for tiny, missing pieces of DNA on the Y chromosome that are essential for sperm production, helping doctors determine the root cause of a very low or zero sperm count.
The Y chromosome contains specific regions of DNA known as Azoospermia Factor (AZF) regions (specifically AZFa, AZFb, and AZFc). These regions contain the genetic blueprints required for normal spermatogenesis (the production and development of sperm). Microdeletions—tiny segments of missing genetic code in these regions—are the second most common genetic cause of male infertility, following Klinefelter syndrome.
Clinical Significance:
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Determining the Cause of Infertility: This test provides a definitive genetic answer for men presenting with non-obstructive azoospermia (complete absence of sperm in the ejaculate) or severe oligozoospermia (a sperm count of less than 5 million per milliliter).
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Guiding IVF and ICSI Treatment: Knowing which specific AZF region is deleted is crucial for family planning. For instance, men with deletions in the AZFc region often still have some sperm in their testes that can be successfully retrieved surgically (via TESE) for use in In Vitro Fertilization (IVF) with Intracytoplasmic Sperm Injection (ICSI). Conversely, complete deletions in the AZFa or AZFb regions generally indicate that surgical sperm retrieval will be unsuccessful, sparing the patient from unnecessary invasive procedures.
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Genetic Counseling: If a man with a Y chromosome microdeletion successfully conceives a male child (usually through ART), that microdeletion will be inherited by the son, who will likely face the same fertility challenges in adulthood.
When is this test recommended?
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Men diagnosed with severe oligozoospermia (< 5 million sperm/mL).
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Men diagnosed with non-obstructive azoospermia (zero sperm count).
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As a mandatory screening step prior to surgical sperm retrieval and assisted reproductive technologies (ART/IVF) for men with unexplained severe infertility.
Sample Requirements:
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Specimen: Whole Blood.
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Container: Lavender Top (EDTA) Tube. This tube contains a preservative that keeps the DNA intact for genetic extraction and PCR (Polymerase Chain Reaction) testing.
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Preparation: No fasting is required.
