ACTN3 genotype influences skeletal muscle mass regulation and response to dexamethasone

Abstract

AbstractHomozygosity for the common ACTN3 null polymorphism (ACTN3 577X) results in α-actinin-3 deficiency in ~20% of humans worldwide and is linked to reduced sprint and power performance in both elite athletes and the general population. α-Actinin-3 deficiency is also associated with reduced muscle mass and strength, increased risk of sarcopenia in the elderly, and altered response to muscle wasting induced by denervation and immobilisation. ACTN3 genotype is also a disease modifier for Duchenne muscular dystrophy (DMD), with α-actinin-3 deficiency associated with slower disease progression. Here we show that α-actinin-3 plays a key role in the regulation of protein synthesis and breakdown..