NEW YORK – A team from the US and Finland has characterized genetic features within and across dozens of domestic cat breeds, tallying the genetic diversity found in the felines, while investigating the prevalence of variants previously implicated in a range of cat diseases or traits.
"This study provides allele frequencies for many disease-associated variants for the first time and provides updates on previously reported information with evidence suggesting that DNA testing has been effectively used to reduce disease-associated variants with certain pedigreed cat populations over time," co-first and corresponding author Heidi Anderson, a researcher with Kinship's Wisdom Panel Research Team, and her colleagues wrote in PLOS Genetics on Thursday.
For their analyses, the researchers used a commercial genotyping array to assess more than 10,400 pedigreed cats and another 617 cats without documented pedigrees, analyzing the genetic data in conjunction with available blood type, physical features, and disease data for the felines. Along the way, they got a look at the frequency of alleles linked to Mendelian diseases and other traits or conditions, while bringing in genetic, phenotype, health record, clinical, and owner interview data for a subset of cats to estimate penetrance patterns of certain variants.
The analyses pointed to a handful of disease-associated variants behind conditions that turned up in the non-pedigreed pets in particular, the researchers reported. In addition, some disease-related variants that were previously considered relatively common in certain cat breeds — including a polycystic kidney disease-related variant in the PKD1 gene that was found in a subset of Persian cats in the past — turned out to be more common in other breeds in the current analysis.
The available genetic data also revealed more than a dozen disease-associated variants that were more common across cat breeds than appreciated in the past, the researchers reported. They found almost four dozen breeds or breed types carrying disease-associated variants that had not been reported in those breeds previously — a set that spanned 13 risk variants.
"[S]everal feline disease-associated variants are more widespread across cat breeds and breed types than previously reported, with both dominant and recessive Mendelian disease-associated variants observed in additional breeds and often at higher allele frequency than the breeds in which they were originally discovered," the authors noted. "This, in part, demonstrates the effectiveness of proactive genetic testing, which has reduced disease-associated variant frequencies in notably affected breeds over time."
Even so, the team noted that genetic diversity tended to be higher in the non-pedigreed cats compared to their pedigreed counterparts, though the extent of the diversity or inbreeding that could be detected varied from one breed to the next.
"As more cats are genotyped, we will learn more about feline variant heritage in the broader domestic cat population, leading to improved healthcare advice for all cat owners," the authors suggested, adding that "[d]irect-to-consumer tests help to further raise awareness of various inherited conditions in cats, provide information that owners can share with veterinarians, and in time … will enable the genetics of common complex feline disease to be deciphered, paving the way for personalized precision healthcare with the potential to ultimately improve welfare for all cats."