Lactate Dehydrogenase A (LDHA)¶

Q: Is LDHA a gene for speed?

'Gene for speed' is a popular label. The research evidence supports an association with racing survivability, but no definite causal link with speed has been established.

The LDHA gene encodes the A subunit of lactate dehydrogenase, a key enzyme of the anaerobic glycolysis pathway. For racing pigeons, whose strength is short bursts of high-intensity flight, LDHA is one of the core genes for understanding "where sprint energy comes from". Based on published peer-reviewed research, this page describes its function, the strength of the evidence and the limits of interpretation.

Plain-language analogy¶

LDHA is like an "emergency generator set" in the muscle: during a climb or a sprint, oxygen supply cannot keep up, the normal aerobic "grid" is not enough, and LDHA immediately starts anaerobic "generation" so the wings can keep working hard. It does not decide whether a pigeon wins a race, but it influences whether energy "keeps coming" through the high-intensity phase.

What LDHA is¶

The LDHA (Lactate Dehydrogenase A) gene encodes the A subunit of lactate dehydrogenase. Lactate dehydrogenase catalyses the reversible conversion between pyruvate and lactate, the final step of anaerobic glycolysis; this step also regenerates NAD⁺, which allows glycolysis to continue under oxygen shortage and thereby maintains ATP supply.

Biological function¶

In skeletal muscle and other high-intensity working tissues, LDH exists mainly as an isoenzyme containing the A subunit, favouring the reduction of pyruvate to lactate;
This process matters especially when oxygen supply cannot keep up with energy demand; it is the "outlet" of anaerobic energy supply;
The relationship between LDHA and movement patterns such as short bursts and sprints is therefore widely discussed in sports science.

Role in racing pigeons¶

Racing pigeon competition includes phases such as cruising, climbing and sprinting. Energy demand rises sharply in the sprint and climb phases, the contribution of anaerobic glycolysis increases, and LDHA activity and expression level may affect the efficiency of energy supply in this phase. It should be stressed that this is an extrapolation based on biochemical function: it is biologically plausible, and it is not a guarantee of race results.

Research evidence (evidence grade B)¶

Ramadan et al. (2018, PLOS ONE): analysed the association between LDHA gene polymorphism and racing survivability in competing pigeons, and found a statistical association between genotype and whether a bird completed the race and homed. PMID: 29775483 | DOI: 10.1371/journal.pone.0195121
Jedrzejczak-Silicka et al. (2021, PLOS ONE): established a PCR-HRM method for genotyping a microsatellite locus in the pigeon LDHA gene, providing a technical route for testing this locus. PMID: 34411134 | DOI: 10.1371/journal.pone.0256065
Saif et al. (2022, bioRxiv preprint): reported an association between the LDHA variant g.2582481G>A and the racing performance of Pakistani pigeons. ⚠️ This paper has not been peer reviewed and is for reference only. DOI: 10.1101/2022.08.14.503877

Evidence grade definition: B = formally published, racing-pigeon-specific statistical association research (see the grade explanation in the Gene Encyclopedia).

Genetic variation and markers¶

Research on LDHA-related variation in racing pigeons involves microsatellite polymorphisms and SNP loci. A genotyping result represents only the genetic marker status an individual carries; interpretation must stay with the association conclusions of the original study and must not be extrapolated beyond the source text.

Scientific limitations¶

Association ≠ causation: racing survivability is affected by many factors, including weather, distance, management and health;
Existing studies have limited population backgrounds and sample sizes, so generalisability awaits more independent research;
"Survivability" is not the same as "speed"; the conclusions on this gene cannot be equated directly with a gene for speed.

Genetic testing and breeding applications¶

The LDHA genotype can serve as one piece of reference information in breeding, used to understand an individual's genetic background at a locus related to energy metabolism. Scientific pairing should take race results, bloodline, multiple gene loci and health data together, and avoid over-interpreting a single gene.

Frequently asked questions¶

Is LDHA a gene for speed?

"Gene for speed" is a popular label. The research evidence supports an association with racing survivability, but no definite causal link with speed has been established.

Can testing for LDHA predict race results?

No. A genotype provides probabilistic information about genetic tendency; it cannot predict or guarantee a specific result.

Does a "good" genotype guarantee a win?

No. Performance is the combined result of genes, training, nutrition, health and environment; a single gene cannot decide a race.

MSTN — negative regulator of muscle development
LRP8 — lipid transport and energy metabolism
GSR — antioxidant defence and stress recovery

References¶

Ramadan S, Miyake T, Yamaura J, Inoue-Murayama M. LDHA gene is associated with pigeon survivability during racing competitions. PLOS ONE. 2018;13(5):e0195121. PMID: 29775483. DOI: 10.1371/journal.pone.0195121
Jedrzejczak-Silicka M, et al. PCR-HRM microsatellite genotyping in LDHA gene of pigeons. PLOS ONE. 2021;16(8):e0256065. PMID: 34411134. DOI: 10.1371/journal.pone.0256065
Saif R, et al. Genetic Association of LDHA Variant g.2582481G>A with Racing Performance of Pakistani Pigeons. bioRxiv. 2022. DOI: 10.1101/2022.08.14.503877 (preprint, not peer reviewed)

← Back to the Gene Encyclopedia · Gene testing on the main site