{{Rsnum
|rsid=1815739
|Gene=ACTN3
|Chromosome=11
|position=66560624
|Orientation=plus
|ReferenceAllele=C
|GMAF=0.3742
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|Summary=muscle performance
|geno1=(C;C)
|geno2=(C;T)
|geno3=(T;T)
|Gene_s=ACTN3
}}{{ population diversity
| geno1=(C;C)
| geno2=(C;T)
| geno3=(T;T)
| CEU | 19.5 | 58.4 | 22.1
| HCB | 34.3 | 45.3 | 20.4
| JPT | 20.4 | 61.9 | 17.7
| YRI | 79.6 | 20.4 | 0.0
| ASW | 63.2 | 36.8 | 0.0
| CHB | 34.3 | 45.3 | 20.4
| CHD | 39.4 | 39.4 | 21.1
| GIH | 13.0 | 58.0 | 29.0
| LWK | 86.4 | 13.6 | 0.0
| MEX | 15.5 | 58.6 | 25.9
| MKK | 64.7 | 30.8 | 4.5
| TSI | 28.4 | 53.9 | 17.6
| HapMapRevision=28
}}This [[SNP]], in the [[ACTN3]] gene, encodes a premature stop codon in a muscle protein called alpha-actinin-3. The polymorphism alters position 577 of the alpha-actinin-3 protein.

In the (C;C) genotype is often called RR. The truncated (T;T) is often called XX. 

{{PMID|18043716|OA=1
}} (T;T) is under-represented in elite strength athletes, consistent with previous reports indicating that alpha-actinin-3 deficiency appears to impair muscle performance.

The most common nucleotide at this position, (C), encodes an arginine (amino acid code R), the alternative T allele encodes a stop codon (X). Hence, the SNP is referred to as R577X, with homozygotes being either RR or XX and heterozygotes being RX. XX individuals completely lack the expression of alpha-actinin-3.

An earlier report studying a relatively small number of Australian elite (i.e. ~Olympic) athletes found that, at least in females, the R allele (ie [[rs1815739]](C)) is associated with sprinters, while the X allele ([[rs1815739]](T)) is associated with endurance athletes. No female or Olympic-level sprinters were XX homozygotes ([[rs1815739]](T;T)). The association tended the same way but was statistically weaker in males. {{PMID|12879365|OA=1
}}

There have been several subsequent studies, but few with large sample sizes and thus few with much statistical power. An example of a typical study: no increase in endurance ability was associated with the X allele in elite male cyclists. {{PMID|16612741}}

An extensive [http://www.wired.com/wiredscience/2008/10/the-gene-for-jamaican-sprinting-success-no-not-really/ blog post] from one of the original authors of this research.

This is one of the SNPs reported by [[NutraHacker SNPs|NutraHacker]].

{{omim
|id=102574
|rsnum=1815739
|variant=0001
}}

{{ClinVar
|rsid=1815739
|Reversed=0
|FwdREF=T
|FwdALT=C
|REF=T
|ALT=C
|RSPOS=66328095
|CHROM=11
|GMAF=0.3745
|dbSNPBuildID=92
|SSR=0
|SAO=1
|VP=0x05016800000017051f110101
|GENEINFO=ACTN3:89
|GENE_NAME=ACTN3
|GENE_ID=89
|WGT=0
|VC=SNV
|CLNALLE=0
|CLNHGVS=NC_000011.9:g.66328095T\x3d
|CLNORIGIN=1
|CLNSRCID=
102574.0001
|CLNSIG=255
|CLNCUI=
|CLNACC=
RCV000019974.1; RCV000019975.26; RCV000019976.26
|Tags=PM;PMC;SLO;VLD;G5A;G5;HD;GNO;KGPhase1;KGPilot123;KGPROD;OTHERKG;PH3;LSD;OM
|CAF=0.3742; 0.6258
|CLNDBN=ACTININ, ALPHA-3 POLYMORPHISM; Actn3 deficiency; Sprinting performance
|CLNSRC=OMIM Allelic Variant
|COMMON=1
|Disease=ACTININ; Actn3 deficiency; Sprinting performance
}}

{{PMID|18852891|OA=1
}} Distribution and effects of nonsense polymorphisms in human genes.

{{PMID|19237423|OA=1
}} Is there an optimum endurance polygenic profile?

{{PMID|19544227}} ACTN3 R577X polymorphism and Israeli top-level athletes.

{{PMID|20005538}} Is the interaction between HIF1A P582S and ACTN3 R577X determinant for power/sprint performance?

{{PMID|20561285}} ACTN3 R577X polymorphism does not influence explosive leg muscle power in elite volleyball players.

{{PMID|20585627|OA=1
}} Web-based, participant-driven studies yield novel genetic associations for common traits.

{{PMID|20845221}} ACTN3 R577X and other polymorphisms are not associated with elite endurance athlete status in the Genathlete study.

{{PMID|20936592}} Association between the ACTN3 R577X polymorphism and female endurance athletes in China.

{{PMID|21407828|OA=1
}} Are 'endurance' alleles 'survival' alleles? Insights from the ACTN3 R577X polymorphism.

{{PMID|21542061|OA=1
}} ACTN3 genotype, athletic status, and life course physical capability: meta-analysis of the published literature and findings from nine studies.

{{PMID|22224919}} ACTN3 R577X polymorphism and performance phenotypes in young Chinese male soldiers.

{{GET Evidence
|gene=ACTN3
|aa_change=Arg577Stop
|aa_change_short=R577X
|impact=not reviewed
|qualified_impact=Insufficiently evaluated not reviewed
|inheritance=unknown
|quality_scores=Array
|dbsnp_id=rs1815739
|n_genomes=1
|n_genomes_annotated=0
|n_haplomes=1
|n_articles=0
|n_articles_annotated=0
|nblosum100=4
|autoscore=1
|webscore=N
}}

{{PMID Auto
|PMID=22891846
|Title=Human alpha-actinin-3 genotype association with exercise-induced muscle damage and the repeated-bout effect.
}}

{{on chip | 23andMe v1}}
{{on chip | 23andMe v2}}
{{on chip | 23andMe v3}}
{{on chip | 23andMe v4}}
{{on chip | FTDNA2}}
{{on chip | HumanOmni1Quad}}
{{on chip | Illumina Human 1M}}