rs2180439

A SNP on chromosome 20. Its most notable genotype is T;T: 2x increased risk of Male Pattern Baldness.

Gene
None listed
Location
Chr 2021,872,462 (GRCh38)
Highest magnitude
3.0Important
Tested on
23andMe, AncestryDNA
Minor allele frequency
44%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. C;CGoodReduced risk of Male Pattern Baldness.Worth knowing · 2.024% of people
  2. C;TBadIncreased risk of Male Pattern Baldness.Worth knowing · 2.547% of people
  3. T;TMost notableBad2x increased risk of Male Pattern Baldness.Important · 3.029% of people

On SNPedia: (C;C), (C;T), (T;T). 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.

  • AverageC;C 24% C;T 47% T;T 29%
  • European ancestry (Utah)C;C 22% C;T 40% T;T 38%
  • Han Chinese (Beijing)C;C 20% C;T 47% T;T 34%
  • Japanese (Tokyo)C;C 15% C;T 44% T;T 41%
  • Yoruba (Nigeria)C;C 25% C;T 40% T;T 36%
  • African ancestry (Southwest US)C;C 25% C;T 51% T;T 25%
  • Chinese (Denver)C;C 14% C;T 50% T;T 37%
  • Gujarati IndianC;C 30% C;T 54% T;T 17%
  • Luhya (Kenya)C;C 30% C;T 50% T;T 20%
  • Mexican ancestry (Los Angeles)C;C 40% C;T 40% T;T 21%
  • Maasai (Kenya)C;C 23% C;T 53% T;T 24%
  • TuscanC;C 22% C;T 53% T;T 26%

Conditions, medicines and genes

Notes

From SNPedia

Notes

spitoon rs2180439(T;T) have 2x increased odds of male pattern baldness.

C;C

Verified in Europeans and Asians. Family Tree DNA reports this as less likely to go bald, but 23andMe doesn't mention it.

C;T

One copy of the risk allele, and one copy of the normal allele. Verified in Europeans and Asians. Family Tree DNA, which tends to skew heterozygous results like this in the most positive light, reports this as less likely to go bald, but 23andMe doesn't mention it.

T;T

Verified in Europeans and Asians. Family Tree DNA reports this SNP as more likely to go bald, but 23andMe doesn't mention it.

Source and license

Adapted from rs2180439 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.