rs3923809

A SNP in the BTBD9 gene on chromosome 6. Its most notable genotype is A;A: 1.9x risk for developing restless legs syndrome

Gene
BTBD9
Location
Chr 638,473,194 (GRCh38)
Highest magnitude
2.0Worth knowing
Tested on
23andMe, AncestryDNA
Minor allele frequency
40%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. A;AMost notableBad1.9x risk for developing restless legs syndromeWorth knowing · 2.038% of people
  2. A;GBadSlightly increased risk of developing restless legs syndromeMinor · 1.545% of people
  3. G;GGoodNormal risk of developing restless legs syndromeMinor · 1.017% of people

On SNPedia: (A;A), (A;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.

Frequency

Share of each genotype in 11 HapMap populations.

  • AverageA;A 38% A;G 45% G;G 17%
  • European ancestry (Utah)A;A 50% A;G 44% G;G 5%
  • Han Chinese (Beijing)A;A 13% A;G 47% G;G 40%
  • Japanese (Tokyo)A;A 13% A;G 46% G;G 41%
  • Yoruba (Nigeria)A;A 45% A;G 46% G;G 10%
  • African ancestry (Southwest US)A;A 47% A;G 44% G;G 9%
  • Chinese (Denver)A;A 21% A;G 47% G;G 32%
  • Gujarati IndianA;A 29% A;G 51% G;G 21%
  • Luhya (Kenya)A;A 56% A;G 39% G;G 5%
  • Mexican ancestry (Los Angeles)A;A 31% A;G 50% G;G 19%
  • Maasai (Kenya)A;A 62% A;G 34% G;G 5%
  • TuscanA;A 47% A;G 47% G;G 6%

Conditions, medicines and genes

Notes

From SNPedia

Show notes, about 970 words

This SNP, located in an intron of the BTBD9 gene, has a variant that is seen somewhat more frequently in individuals with restless legs syndrome. The risk allele is rs3923809(A); carriers of two such alleles, i.e. those with rs3923809(A;A) genotypes, are estimated to be 1.9 fold more likely to have restless legs syndrome than rs3923809(G;G) individuals. The authors of this study suggest that perhaps half of the cases of restless legs syndrome may involve the rs3923809 risk genotypes. Consistent with this finding, another report about rs3923809 links the (G) minor allele to a lower frequency of restless legs syndrome with an overall odds ratio of 0.57 (CI: 0.48-0.68). Note that 70-80% of all individuals in European populations carry one or two copies of the (A) major allele, yet restless legs syndrome is thought to affect less than 10% of all adults. Therefore, although an individual may be at higher risk based on their genotype, the genotype by itself certainly isn't able to predictably cause restless legs syndrome. The association between rs3923809 and RLS has been replicated in three European populations, and shows the most consistent effect across populations of several SNPs studied. The results of a 2013 study of Korean patients suggest that the role of BTBD9 in the pathogenesis of restless legs syndrome is more universal across populations than previously reported and more efforts should be focused on the role of epistasis in the genetic architecture of restless legs syndrome. A significant association was found for rs3923809 and rs9296249 in BTBD9. Association of restless legs syndrome variants in Korean patients with restless legs syndrome.

A;A

rs3923809 is a A/G variation on human chromosome 6. Associated with: Restless legs syndrome. This SNP, located in an intron of the BTBD9 gene, has a variant that is seen somewhat more frequently in individuals with restless legs syndrome. The risk allele is rs3923809(A); carriers of two such alleles, i.e. those with rs3923809(A;A) genotypes, are estimated to be 1.9 fold more likely to have restless legs syndrome than rs3923809(G;G) individuals. The authors of this study suggest that perhaps half of the cases of restless legs syndrome may involve the rs3923809 risk genotypes. Note that 70-80% of all individuals in European populations carry one or two copies of the (A) major allele, yet restless legs syndrome is thought to affect less than 10% of all adults. Therefore, although an individual may be at higher risk based on their genotype, the genotype by itself certainly isn't able to predictably cause restless legs syndrome. The association between rs3923809 and RLS has been replicated in three European populations, and shows the most consistent effect across populations of several SNPs studied. The results of a 2013 study of Korean patients suggest that the role of BTBD9 in the pathogenesis of restless legs syndrome is more universal across populations than previously reported and more efforts should be focused on the role of epistasis in the genetic architecture of restless legs syndrome. A significant association was found for rs3923809 and rs9296249 in BTBD9. Association of restless legs syndrome variants in Korean patients with restless legs syndrome.

A;G

rs3923809 is a A/G variation on human chromosome 6. Associated with: Restless legs syndrome. This SNP, located in an intron of the BTBD9 gene, has a variant that is seen somewhat more frequently in individuals with restless legs syndrome. The risk allele is rs3923809(A); carriers of two such alleles, i.e. those with rs3923809(A;A) genotypes, are estimated to be 1.9 fold more likely to have restless legs syndrome than rs3923809(G;G) individuals. The authors of this study suggest that perhaps half of the cases of restless legs syndrome may involve the rs3923809 risk genotypes. Consistent with this finding, another report about rs3923809 links the (G) minor allele to a lower frequency of restless legs syndrome with an overall odds ratio of 0.57 (CI: 0.48-0.68). Note that 70-80% of all individuals in European populations carry one or two copies of the (A) major allele, yet restless legs syndrome is thought to affect less than 10% of all adults. Therefore, although an individual may be at higher risk based on their genotype, the genotype by itself certainly isn't able to predictably cause restless legs syndrome. The association between rs3923809 and RLS has been replicated in three European populations, and shows the most consistent effect across populations of several SNPs studied. The results of a 2013 study of Korean patients suggest that the role of BTBD9 in the pathogenesis of restless legs syndrome is more universal across populations than previously reported and more efforts should be focused on the role of epistasis in the genetic architecture of restless legs syndrome. A significant association was found for rs3923809 and rs9296249 in BTBD9. Association of restless legs syndrome variants in Korean patients with restless legs syndrome.

G;G

rs3923809 is a A/G variation on human chromosome 6. Associated with: Restless legs syndrome. This SNP, located in an intron of the BTBD9 gene, has a variant that is seen somewhat more frequently in individuals with restless legs syndrome. The risk allele is rs3923809(A); carriers of two such alleles, i.e. those with rs3923809(A;A) genotypes, are estimated to be 1.9 fold more likely to have restless legs syndrome than rs3923809(G;G) individuals. The authors of this study suggest that perhaps half of the cases of restless legs syndrome may involve the rs3923809 risk genotypes. Consistent with this finding, another report about rs3923809 links the (G) minor allele to a lower frequency of restless legs syndrome with an overall odds ratio of 0.57 (CI: 0.48-0.68).

Source and license

Adapted from rs3923809 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.

SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.