The genetic research goes on: New gene dopamine receptor type 4 influences racing performance

As an increasing number of top lofts are trying to predict the level of performance and the value of their breed through genetic testing, the influence of this LDHA gene only becomes more and more apparent.

After all, we already knew that the rare A variant of the LDHA gene has a clear influence on the level of performance of racing pigeons, and this had been scientifically validated as well. One remarkable example is top breeding hen “Yelena” of Etienne Meirlaen; this hen appears to have the very rare LDHA A/A genotype.

“Yelena” BE06-4288297 is for instance the dam of:

1° Int. & Nat. Narbonne
4° Nat. Montauban
5° Nat. Montauban
6° Nat. Ace Bird Extreme Long Distance KBDB Yearlings '14
7° Nat. Montauban
10° Nat. Montauban
11° Nat. Narbonne
12° Nat. Montauban
14° Nat. Agen

Grandmother of:

3° Nat. Agen
9° Nat. Ace Bird Extreme Long Distance KBDB Yearlings '14
11° Int. Agen
13° Nat. Narbonne

It would be an understatement to say that this is remarkable, especially because this genotype is so rare. The homozygote A/A is rare even among the very best pigeons (appr. 5%). If we were to test 100 normal (average) racing pigeons, the chances of finding an A/A are next to none. The A/B heterozygote will be low in number as well (appr. 10%). There is a 30-40% occurrence of A/B among absolute top class pigeons (notice that among these top pigeons there is still more than 50% B/B). We already knew that from a previous article which you can read again here.

The superbreeder "Superboy" of the Scheele brothers is homozygote A/A as well.

Superboy NL02-0274336 (LDHA A/A) is for instance the sire of:

1st NPO Orleans 5000 pigeons (Blauwe Orleans)
1st Peronne 6793 pigeons (Amy)
1st Orleans 5149 pigeons (Kim)
1st NPO Poitiers 2183 pigeons (Ace Girl)
1st Pommeroeul 2066 pigeons (Boy)
1st Peronne 550 pigeons (Amy)
1st Chateaudun 947 pigeons (Elke)
2nd NPO Tours 2011 (Magic Boy)
2nd NPO Chateauroux 2012 (Ace Girl)
2nd NPO La Souterraine 2012 (Ace Girl)
2nd NPO Argenton 2009 (Aria)
2nd NPO Chateauroux 2008 (Thor)
3rd NPO Argenton 2011 (Magic Boy)
6th Nat. Ace Youngsters (Piet)
1st Nat. Ace Long Distance 2011 (Magic Boy)
1st Ace Middle Distance Youngsters Department Zeeland (Super 02)
1st Ace Middle Distance Youngsters Department Zeeland (Lieke)
1st Ace Middle Distance Youngsters Department Zeeland Jong (Boy)
1st Gouden Crack FZN Jong (Lieke)

Grandchildren:

1st NPO Argenton 3973 pigeons (Fast Boy)
1st NPO Orleans 6842 pigeons (Akira)
1st NPO La Souterraine 3469 pigeons (Mariah)
1st Peronne 7007 pigeons (Amy)
1st Alblis 7889 pigeons (Alblis Boy)
1st Orleans 4927 pigeons (800)
1st Sezanne 8785 pigeons (Ace Boy)
1st Arras 2012 pigeons (Ace Boy)
1st Sourdun 1558 pigeons (Mighty Mike)
1st Peronne 1297 pigeons (Ace Boy)
1st Pithiviers 1261 pigeons (Ace Boy)
1st Niergnies 1183 pigeons (Demi)
1st Peronne 1066 pigeons (Fast Boy)
1st Orleans 1030 pigeons (Dylan)
1st Orleans 746 pigeons (Mighty Mike)
1st Nanteuil 624 pigeons (Dylan)
4th Nat. Ace Long Distance 2011 (Ace Boy)
1st Ace Long Distance Department Zeeland 2011 (Ace Boy)
1st Ace Long Distance Department Zeeland 2012 (Ablis Boy)
1st Ace Natour Department Zeeland 2012 (Demi)
1st Gouden Crack FZN 2011 (Ace Boy)

Some top breeds (not limitative) like Bricon Loft (BE) and Marijke Vink (Mookhoek, NL) use genetic testing to improve the breeding value of their pigeon families.

For example, “Gerard” of Marijke Vink is LDHA A/B. This small loft has in general a very high percentage of the A variant (more than 50%!).

“Gerard” NL12-1597920 has won:

2nd Peronne 18,538 pigeons
2nd Sens    14,517 pigeons
5th Peronne  2,741 pigeons
5th Bourges  2,329 pigeons
9th Peronne  9,929 pigeons

New gene dopamine receptor type 4 (DRD4) is scientifically proven to influence the racing performance of pigeons

In the meantime a new gene has been discovered with a very clear influence on racing capability nl. a dopamine receptor gene. Dopamine receptors are found in the brain and their function is to transfer signals of the neurotransmitter dopamine in specific zones inside the brain. Variations in this gene have been associated in humans and animals with character treats and certain mental capabilities. In humans for example this receptor has been associated with creativity, susceptibility for depression, etc.

In this recently published research (in the scientific magazine “Animal Genetics”) a number of different variations were found in this gene in racing pigeons, of which two were relevant for racing performance. It has proven to be influential in all distances, but the difference was statistically significant only in the sprint and middle distance races. In this study 1380 racing records were taken into account. (Proskura et al, 2015)

The variant CCCC was associated with the lowest average in racing performances. The variants CTCC and CCCT showed higher averages (statistically significant), and the CTCT variant clearly had a very high average in racing performances. This was significantly proven in the sprint and the middle distance. The level of performance was also higher in the long distance but there was no scientific proof for this. Further research will have to give more clarity on that.

Based on our findings we believe there will a similar influence in the longer distance, since we found a homozygote TT in a 1st Ace Pigeon extreme long distance of Belgium; this had never been found before, not even in the major studies carried out by Animal Genetics. In any case the CT variant is found a lot more in Ace pigeons.

It is very clear that DNA research is increasingly helping us to know more about the true genetic qualities of racing pigeons, besides performance, pedigree and external properties. This is particularly the case for a pigeon's breeding value.