A novel 31-bp indel in the <i>paired box 7</i> (<i>PAX7</i>) gene is associated with chicken performance traits

<div><p></p><p>1. A novel 31-bp indel polymorphism in intron 3 of the chicken <i>paired box 7</i> (<i>PAX7</i>) gene was identified and genotyped in an F₂ resource population of Gushi chicken crossed with Anka broiler to analyse its associations with chicken growth, carcass and meat quality traits.</p><p>2. Results showed that the 31-bp indel was significantly associated with body weight at 4, 6, 8, 10, 12 weeks of age and body size indices including shank length, shank girth, body slanting length at 8 and 12 weeks of age. Significant associations were found for carcass weight, semi-evisceration weight, evisceration weight, breast muscle fibre diameter, leg muscle fibre diameter, breast muscle fibre density, while no significant association with leg muscle fibre density was observed.</p><p>3. It was concluded that the 31-bp indel in intron 3 of the <i>PAX7</i> gene was associated with chicken growth, carcass and meat quality traits where the 31-bp deletion had a negative effect on chicken growth and carcass traits and positive effect on meat quality traits.</p>