rs1050565

A SNP in the BLMH gene on chromosome 17. Its most notable genotype is C;C: if testicular cancer patient, 5x poorer response to bleomycin chemotherapy

Gene
BLMH
Location
Chr 1730,249,058 (GRCh38)
Highest magnitude
2.0Worth knowing
Tested on
23andMe, AncestryDNA, FamilyTreeDNA
Minor allele frequency
27%

Genotypes

Plus strand, as in 23andMe and AncestryDNA files.

  1. T;TGoodnormalTypical · 0.060% of people
  2. C;TNot ratednormalTypical · 0.034% of people
  3. C;CMost notableBadif testicular cancer patient, 5x poorer response to bleomycin chemotherapyWorth knowing · 2.06% of people

SNPedia records rs1050565 on the minus strand: (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.

  • AverageT;T 60% C;T 34% C;C 6%
  • European ancestry (Utah)T;T 44% C;T 48% C;C 8%
  • Han Chinese (Beijing)T;T 77% C;T 20% C;C 3%
  • Japanese (Tokyo)T;T 65% C;T 27% C;C 9%
  • Yoruba (Nigeria)T;T 73% C;T 23% C;C 4%
  • African ancestry (Southwest US)T;T 65% C;T 33% C;C 2%
  • Chinese (Denver)T;T 81% C;T 17% C;C 2%
  • Gujarati IndianT;T 60% C;T 35% C;C 5%
  • Luhya (Kenya)T;T 52% C;T 36% C;C 12%
  • Mexican ancestry (Los Angeles)T;T 48% C;T 43% C;C 9%
  • Maasai (Kenya)T;T 45% C;T 43% C;C 12%
  • TuscanT;T 47% C;T 48% C;C 5%

Conditions, medicines and genes

Notes

From SNPedia

Show notes, about 220 words

Testicular cancer patients may be treated with bleomycin, a cytotoxic drug that is essential component of chemotherapy regimens for this cancer, officially known as disseminated testicular germ-cell cancer (TC). rs1050565 is a SNP in the BLMH gene. This gene encodes a protein that can inactivate bleomycin. Based on a study of 300 TC patients treated with bleomycin, a testicular cancer patient with a rs1050565(G;G) genotype has an odds ratio of 4.97 (CI: 2.17 - 11.39) for TC-related death compared to (A;G) or (A;A) genotypes. The rs1050565(G;G) genotype also shows a higher prevalence of early relapses.

C;C

Testicular cancer patients may be treated with bleomycin, a cytotoxic drug that is essential component of chemotherapy regimens for this cancer, officially known as disseminated testicular germ-cell cancer (TC). rs1050565 is a SNP in the BLMH gene. This gene encodes a protein that can inactivate bleomycin. Based on a study of 300 TC patients treated with bleomycin, a testicular cancer patient with a rs1050565(G;G) genotype has an odds ratio of 4.97 (CI: 2.17 - 11.39) for TC-related death compared to (A;G) or (A;A) genotypes. The rs1050565(G;G) genotype also shows a higher prevalence of early relapses. Note that this gene affects bleomycin metabolism; the GG does not mean that a person is more likely to get testicular cancer.

Source and license

Adapted from rs1050565 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.