Now, the first complete analysis of bulldog genetics, published July 28 in , reveals that the breed has very low genetic diversity.
Selected regions of the genome were examined using a SNP scan of 148 breeds. Using association analysis, several QTL were identified for size (WT) and shape (HT and residuals of WT0.33 regressed on to height). presents the location and characterization of the loci for which the most evidence was accrued. Loci regulating both height-at-the-withers and body weight are located on Canis familiaris autosome (CFA) 7, 10, 15, and 34, whereas the locus on CFA 9 regulates only body weight. When Wt0.33 is regressed onto height at the withers, a variation in shape can be distinguished that represents differences between breeds that range from dogs that are thin for their height (pursuit hounds such as the greyhound, Afghan hound, or whippet, as well as some smaller dogs such as the fox terrier) to ones that have a large body mass for their height (see supplemental Figure 3). The locus on CFA 6, associated with this phenotype, was not associated with either height or weight. In the Portuguese water dog (), a highly significant locus on CFA 12 that regulates an inverse correlation between limb bone length and width was identified. This locus was not identified with genomewide significance in the present across-breeds WT0.33 residual scan, but it was found in that scan at a significance that validated the pre-identified locus from the Portuguese water dog. Such instances of lowered significance may reflect a low frequency of breeds in which a locus has been fixed.
Considerable population structure exists among dog breeds (). Using the popgen () package of R, we estimated measures of diversity among these breeds (). The mean “c” (analogous to FST) value is 0.25 with individual breed values ranging from 0.05 to 0.61. In an across-breed association analysis, noncausative (shadow) loci may result from effects of population substructure due to genetic relatedness among breeds. To test for this, we used a mixed-model analysis (see ) to predict trait values of weight as well as head:body ratio (head ratio). We found that all of the significant QTL for weight or head ratio () remained significant in a mixed model correcting for genetic relatedness of breeds, with P-values ranging from 10−2 to −5 for weight and −3 for the three significant head/rat loci.
Genomic Analyses of Modern Dog Breeds - NCBI - NIH
[Analysis of the prevalence of distichiasis in the dog breed Elo]
But Fortune had a big question: Do these tests actually work? Short of becoming a geneticist and analyzing the DNA yourself, if you have a mixed breed rescue, how can you know whether any of this is legit? I decided to try out the two brands currently available and see if they gave matching results for my dog, Addie. What happens once my dog’s blood sample is received? Once our lab receives the dog’s blood sample, it undergoes extensive analysis. Our proprietary algorithm involves more than 18,000,000 comparisons against more than 250 different breeds and over 1800 genetic markers. Once the analysis is completed, we generate two reports: a general overview of the results for the pet owner, and a more detailed, medically-focused report for your veterinarian. Once you receive the reports, you should schedule a consultation with your veterinarian to review the report.