Infertility associated with two accessory bisatellited chromosomes.

Area of Science:

• Human Genetics
• Reproductive Biology
• Cytogenetics

Background:

• Oligoasthenospermia, characterized by low sperm count and motility, affects male fertility.
• Chromosomal abnormalities can contribute to impaired spermatogenesis.
• Bisatellited chromosomes, specifically inverted duplications of chromosome 15 (inv dup(15)), are rare structural variations.

Observation:

• An oligoasthenospermic male was identified with two extra bisatellited chromosomes: inv dup(15)(pter----q11.2::q11.2----pter).
• Analysis revealed significantly increased nucleolar organizer region (NOR) activity in the patient compared to a fertile brother.
• The patient also exhibited a higher frequency of satellite associations.

Findings:

• Increased NOR activity was directly observed in the patient with the inv dup(15) abnormality.
• A higher frequency of satellite associations was noted in the index case.
• No direct correlation was found between NOR activity levels and the frequency of satellite associations.

Implications:

• Elevated NOR activity and increased satellite associations may predispose individuals to gametogenic impairment.
• This study suggests a potential link between specific chromosomal rearrangements and male infertility.
• Further research is warranted to elucidate the mechanisms by which these chromosomal factors affect sperm development.