rs4950928

A SNP in the CHI3L1 gene on chromosome 1. Its most notable genotype is C;G: Half the risk (maybe) of Asthma.

Gene
CHI3L1
Location
Chr 1203,186,754 (GRCh38)
Highest magnitude
2.0Worth knowing
Tested on
23andMe, AncestryDNA
Minor allele frequency
21%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. C;CBadNormal (higher) risk of Asthma.Minor · 1.963% of people
  2. C;GMost notableGoodHalf the risk (maybe) of Asthma.Worth knowing · 2.031% of people
  3. C;GGoodHalf the risk (maybe) of Asthma.Worth knowing · 2.031% of people
  4. G;GGoodHalf the risk (maybe) of Asthma.Worth knowing · 2.05% of people

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

Frequency

Share of each genotype in 4 HapMap populations.

  • AverageC;C 63% C;G 31% C;G 31% G;G 5%
  • European ancestry (Utah)C;C 66% C;G 33% C;G 33% G;G 2%
  • Han Chinese (Beijing)C;C 73% C;G 20% C;G 20% G;G 7%
  • Japanese (Tokyo)C;C 68% C;G 30% C;G 30% G;G 2%
  • Yoruba (Nigeria)C;C 46% C;G 44% C;G 44% G;G 11%

Conditions, medicines and genes

Notes

From SNPedia

Notes

rs4950928 in CHI3L1 is likely to play roles in the predisposition to schizophrenia. An attempt to repeat the association between rs4950928 and risk for schizophrenia in an ethnically identical population (Japanese) as well as a new population (Han Chinese) failed to show any significant association. In contrast to previous studies, in this study of 6514 Danish adults the rs4950928(G) allele - rather than the (C) allele - was found to be associated with asthma.

C;G

One study found a 0.54x lower risk for Asthma for this allele.

C;G

One study found a 0.54x lower risk for Asthma for this allele.

G;G

One study found a 0.54x lower risk for Asthma for this allele.

Source and license

Adapted from rs4950928 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.