A pericentric inversion in the cattle Y chromosome

Area of Science:

• Veterinary Genetics
• Cytogenetics
• Mammalian Reproduction

Background:

• Podolian cattle exhibit diverse genetic traits.
• Phenotypic variations in cattle can sometimes be linked to chromosomal abnormalities.
• Understanding Y chromosome structure is crucial for male fertility and sex determination.

Purpose of the Study:

• To investigate the cytogenetic basis of a female-like phenotype in a male Podolian cattle.
• To identify chromosomal abnormalities, specifically in the Y chromosome, in affected cattle.
• To characterize the nature and origin of any observed Y chromosome anomalies.

Main Methods:

• Cytogenetic analysis of male Podolian cattle (n=16), including two sires and 14 male offspring.
• Banding techniques (e.g., G-banding, C-banding) for chromosome visualization.
• Fluorescence in situ hybridization (FISH) mapping using Y-specific molecular markers.

Main Results:

• Eleven male offspring and one sire carried an abnormal Y chromosome.
• The abnormality was identified as a pericentric inversion involving the proximal half of the Yq arm (Yq11 to Yq12.2).
• Both banding and FISH confirmed the Y chromosome inversion, with Y-specific markers localizing to the inverted region.

Conclusions:

• A pericentric inversion of the Y chromosome (Yq11-->q12.2) is present in a subset of male Podolian cattle.
• This chromosomal aberration was found in male offspring exhibiting a female-like phenotype, suggesting a potential link.
• The study highlights the importance of cytogenetic investigation in understanding phenotypic variations and chromosomal anomalies in cattle breeding.