The effect on performance in sports in descendents of CLCN1 gene mutation carrier New Forest pony stallions

Abstract

Aim of the study: To determine if ponies descending from a CLCN1 gene mutation carrier stallion perform better in sports, compared to ponies that do not descent from a CLCN1 gene mutation carrier stallion. Study design: Data analysis of 11.414 New Forest ponies, in which the relationship between the descent of the ponies and their sport performance are analyzed. Methods: Ponies were divided in jumping, dressage and eventing categories. They were listed categorically from the lowest category to the highest and descendents from mutation carrier stallions were marked. Statistical analysis with logistic regression between the sport categories and within the categories has been performed using SPSS version 19. Significance was set at p < 0.05. Results: Ponies descending from a mutation carrying stallion are significantly better performing in jumping. The odds of finding a descent in the highest jumping category is 7.6 compared to the lowest. In dressage, descendents from a gene mutation carrier stallion are performing significantly better, with an odds of 4.1 for performing in the highest category. In eventing, the odds of finding a descendent from a mutation carrying stallion in the highest category is 2.9 compared to the lowest. Conclusion and clinical relevance: Ponies that are descendants of a mutation carrying stallion are performing significantly better in jumping, dressage and eventing. This conclusion might lead to breeding programs which includes stallions who carry this mutation, aiming to breed better performing ponies in equine sports, which is in contrast of the aim of the Studbook to eradicate the mutation.