rs688
A SNP in the LDLR gene on chromosome 19. Its most notable genotype is C;C: normal risk
- Gene
- LDLR
- Location
- Chr 1911,116,926 (GRCh38)
- Highest magnitude
- 0.0Typical
- Tested on
- 23andMe, FamilyTreeDNA
- Minor allele frequency
- 28%
Genotypes
As shown in 23andMe and AncestryDNA files.
- C;CMost notableGoodnormal risk
- C;TNot ratednormal risk for Alzheimer's; higher total and LDL cholesterol in females
- T;TNot rated1.5x higher risk for males of Alzheimer's; higher total and LDL cholesterol in females
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 62% C;T 31% T;T 7%
- European ancestry (Utah)C;C 35% C;T 44% T;T 20%
- Han Chinese (Beijing)C;C 75% C;T 20% T;T 4%
- Japanese (Tokyo)C;C 71% C;T 27% T;T 3%
- Yoruba (Nigeria)C;C 95% C;T 5% T;T 0%
- African ancestry (Southwest US)C;C 68% C;T 32% T;T 0%
- Chinese (Denver)C;C 66% C;T 30% T;T 4%
- Gujarati IndianC;C 39% C;T 46% T;T 16%
- Luhya (Kenya)C;C 93% C;T 7% T;T 0%
- Mexican ancestry (Los Angeles)C;C 28% C;T 59% T;T 14%
- Maasai (Kenya)C;C 80% C;T 19% T;T <1%
- TuscanC;C 32% C;T 56% T;T 12%
Related
Conditions, medicines and genes
Other LDLR SNPs
- rs121908027-;-familial hypercholesterolemiaVery important
- rs5933C;GFamilial HypercholesterolemiaVery important
- rs2228671A;CFamilial HypercholesterolemiaVery important
- rs2569548C;TFamilial HypercholesterolemiaVery important
- rs11547917A;CFamilial HypercholesterolemiaVery important
- rs13306512A;CFamilial HypercholesterolemiaVery important
- rs13306515A;CFamilial HypercholesterolemiaVery important
- rs28941776A;GFamilial HypercholesterolemiaVery important
Notes
From SNPedia
Show notes, about 400 words
RNA made containing the rs688(T) SNP, a variant near exon 12 of the low-density lipoprotein receptor (LDLR) that is a receptor for ApoE proteins, is spliced at lower efficiency in males. Presumably due to this, the rs688(T;T) genotype was associated with increased risk for Alzheimer's disease odds in males (odds ratio 1.49, CI: 1.13-1.97, uncorrected p=0.005), but not in females. The presence of the rs688(T) allele associates with increased total and LDL-cholesterol in female members of the Framingham Offspring Study; rs688 was not associated with significant differences in HDL-cholesterol. The largest rs688-associated cholesterol differences were observed in pre-menopausal women. Taken together, rs688, a SNP present in approximately 60% of Caucasians, is associated with significant 10% increases in total and LDL-cholesterol in pre-menopausal women. SNP genotyping on a genome-wide amplified DOP-PCR template. Genome wide association (GWA) study for early onset extreme obesity supports the role of fat mass and obesity associated gene (FTO) variants. Genome-wide association study identifies genes for biomarkers of cardiovascular disease: serum urate and dyslipidemia. Lifelong reduction of LDL-cholesterol related to a common variant in the LDL-receptor gene decreases the risk of coronary artery disease--a Mendelian Randomisation study. Genetic-epidemiological evidence on genes associated with HDL cholesterol levels: a systematic in-depth review. Development of a fingerprinting panel using medically relevant polymorphisms. Genetic determinants of serum lipid levels in Chinese subjects: a population-based study in Shanghai, China. Analysis of recently identified dyslipidemia alleles reveals two loci that contribute to risk for carotid artery disease. The role of HMGCR alternative splicing in statin efficacy. Genomic features defining exonic variants that modulate splicing. Role of SFRS13A in low-density lipoprotein receptor splicing. Population based allele frequencies of disease associated polymorphisms in the Personalized Medicine Research Project. Expression and regulation of a low-density lipoprotein receptor exon 12 splice variant. Exploring genetic determinants of plasma total cholesterol levels and their predictive value in a longitudinal study. Genetic loci associated with lipid concentrations and cardiovascular risk factors in the Korean population.
Source and license
Adapted from rs688 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.