FISH analysis with locus-specific probes in sperm from two translocation carrier men

Area of Science:

• Genetics
• Human Reproduction
• Cytogenetics

Background:

• Balanced reciprocal translocations are chromosomal abnormalities affecting fertility.
• Understanding meiotic segregation in carriers is crucial for genetic counseling.
• Aneuploidy risk assessment in offspring is a significant concern for translocation carriers.

Purpose of the Study:

• To analyze meiotic segregation patterns in sperm from two men with balanced reciprocal translocations.
• To evaluate the utility of dual-colour fluorescence in situ hybridisation (FISH) for this analysis.
• To determine the frequency of different segregation modes and their relation to aneuploidy risk.

Main Methods:

• Sperm samples from two balanced reciprocal translocation carriers were analyzed.
• Dual-colour fluorescence in situ hybridisation (FISH) with chromosome-specific probes was employed.
• 1000 spermatozoa per probe were analyzed to determine segregation modes (alternate, adjacent-1, adjacent-2).

Main Results:

• The study analyzed specific translocations: t(4;8)(p15;p12) and t(15;22)(q23;q13.2).
• Mean frequencies for alternate and/or adjacent-1 segregation were 69.47%.
• Mean frequencies for adjacent-2 and alternate/adjacent-2 segregation were 30.51% and 78.70%, respectively.

Conclusions:

• Fluorescence in situ hybridisation (FISH) is an effective method for analyzing meiotic segregation products.
• This technique aids in assessing aneuploidy risk for individuals with reciprocal translocations.
• The findings contribute to understanding the reproductive implications of chromosomal translocations.