Performance Testing for Pigeons DRD4a and DRD4b analysis
In 2015, research published in the Journal of Animal Genetics showed a relationship between the gene encoding the dopamine receptor D4 (DRD4) and racing performance in pigeons. In this study, the results of 1380 race records from 8 (<400 km) and 6 long (> 500 km) races were processed. The study revealed a few different variations in the type 4 dopamine receptor gene, two of which were relevant to racing performance. Variations in DRD4 were found to affect performance at all distances, but only on high and medium distances was the difference statistically significant.
Currently, analyses are focused on two SNP polymorphisms, SNP g.129954C> T (also referred to as DRD4a) and SNP g.129456C> T (also referred to as DRD4b). The variant CC/CC (DRD4a/DRD4b) was associated with the lowest overall mean in racing performances. The variants CT/CC and CC/CT had higher statistically significant averages; and the CT/CT variant had a very high mean in racing performance. This was significantly proven on speed and middle distance (<400km). In a longer distance (>500 km) the mean was higher, but this was not be proven statistically in the study.
Recent studies investigating the DRD2 receptor in pigeons published by the Japan Poultry Science Association suggest that the C4532T SNP located in exon 6 of the DRD2 gene is closely related to the reproductive properties of pigeons. In addition, individuals with genotype AB had significantly higher fertility rates and overall hatching rates for 500 days than birds with genotype AA.
| g.129954C> T (DRD4a) | |
| TT | The individual carries 2 copies of the T allele, is homozygous for DRD4a TT. The pigeon is statistically more powerful and achieves better racing performance. An individual passes on only the T allele to his offspring |
| CT | The individual carries both the C and T alleles and is heterozygous. The pigeon is a statistically better racing pigeon on short tracks. The individual can pass on to either the C or T allele |
| CC | The individual carries two copies of the C allele and is therefore homozygous for C. The pigeon transmits only the C allele to the offspring |
| g.129456C> T (DRD4b) | |
| TT | The individual carries 2 copies of the T allele, is homozygous for DRD4b TT. The pigeon is statistically more powerful and achieves better racing performance. An individual passes on only the T allele to his offspring |
| CT | Jedinec nesie obidve alely C aj T, je heterozygot. Jedinec je štatisticky lepším pretekárskym holubom na krátke trate. Jedinec môže odovzdať potmstvu buď alelu C alebo T |
| CC | The individual carries two copies of the C allele and is therefore homozygous for C. The pigeon transmits only the C allele to the offspring |
SAMPLE: The analysis is performed from a bloodstain or freshly plucked chest feathers of about 6 pieces, as well as for analysis of bird sexing
