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Insertional polymorphisms of endogenous feline leukemia viruses
Alfred L Roca1, William G Nash, Joan C Menninger
1Laboratory of Genomic Diversity, Basic Research Program, SAIC-Frederick, Maryland, USA. roca@ncifcrf.gov
Journal of Virology
|March 16, 2005
Summary
Domestic cats possess numerous endogenous feline leukemia virus (enFeLV) copies integrated into their genomes. Genomic variations in these enFeLVs may influence feline leukemia virus leukemogenesis.
Area of Science:
- Genetics
- Virology
- Comparative Genomics
Background:
- Endogenous feline leukemia viruses (enFeLVs) are integrated retroviral sequences found in the feline genome.
- Understanding the distribution and variation of enFeLVs is crucial for studying their potential impact on feline health, particularly leukemogenesis.
Purpose of the Study:
- To determine the number, chromosomal distribution, and insertional polymorphisms of enFeLVs in domestic cats.
- To investigate the potential role of enFeLV genomic variation in feline leukemia virus (FeLV) leukemogenesis.
Main Methods:
- Fluorescent in situ hybridization (FISH) was employed to visualize enFeLV loci.
- Radiation hybrid mapping was utilized to determine the chromosomal locations of enFeLVs.
- Analysis was performed on four domestic cat breeds: Burmese, Egyptian Mau, Persian, and a non-breed.
Main Results:
- Twenty-nine distinct enFeLV loci were identified across 12 of 18 autosomes in the studied cats.
- Each cat harbored enFeLV at 9–16 loci, with an average of 19 autosomal copies per diploid genome.
- Significant variation in enFeLV distribution was observed, with only one autosomal locus (B4q15) consistently present in both homologs across all cats. enFeLVs were also detected on the X and Y chromosomes.
Conclusions:
- The feline genome contains a variable number of enFeLV loci with diverse chromosomal distributions.
- Telomeric localization of some enFeLV loci suggests a role for ectopic recombination in their distribution.
- Genomic variation in enFeLVs presents a potential genetic factor influencing susceptibility to FeLV-induced leukemogenesis in cats.
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