Numerical chromosome abnormalities are associated with sperm tail swelling patterns.

Area of Science:

• Reproductive Biology
• Human Genetics
• Spermatozoa Analysis

Background:

• Sperm aneuploidy is a significant factor in male infertility and recurrent pregnancy loss.
• Assessing sperm aneuploidy is crucial for reproductive medicine.
• Hypo-osmotic swelling (HOS) is a test of sperm membrane integrity and tail function.

Purpose of the Study:

• To determine if differential sperm tail swelling patterns after hypo-osmotic shock can distinguish normal sperm from aneuploid sperm.
• To investigate the relationship between sperm tail swelling patterns and aneuploidy rates.

Main Methods:

• A prospective study combining fluorescence in situ hybridization (FISH) with hypo-osmotic swelling (HOS) for simultaneous assessment of human spermatozoa aneuploidy and viability.
• FISH analysis was performed for chromosomes 1, 13, 18, 21, X, and Y.
• Scored 16,473 sperm cells from fertile donors and patients with oligoasthenoteratozoospermia (OAT).

Main Results:

• Sperm exhibiting tail-tip swelling patterns showed a 17.2-fold decrease in total aneuploidy frequency compared to nonselected sperm in OAT patients.
• Screening sperm with tail-tip swelling patterns from OAT patients revealed a frequency of total aneuploidy four times lower than in nonselected sperm from fertile donors.

Conclusions:

• Sperm cells displaying tail-tip swelling patterns are associated with a low frequency of aneuploidy.
• Tail-tip swelling patterns may serve as a useful indicator for identifying sperm with a lower likelihood of aneuploidy.