rs2281845: Understanding Genetic Associations with Tooth Eruption
The genetic variant rs2281845 is a single nucleotide polymorphism located on chromosome 1q32.1. Research has identified an association between the T allele of this variant and a slight reduction in the number of permanent teeth erupted in children between the ages of 6 and 14.
What each genotype means
Typical tooth eruption timing
This genotype is considered the major allele configuration in many populations. Research indicates that individuals with this profile do not carry the specific genetic association linked to a reduction in the number of permanent teeth erupted between the ages of 6 and 14.
This is the most common genotype globally, though frequencies vary significantly by ancestral background.
Intermediate tooth eruption profile
Carrying one copy of the G allele means you have an intermediate genetic profile regarding the timing of permanent tooth eruption. Statistical associations suggest that the influence of this variant on tooth development is primarily linked to the presence of the alternative allele, and this heterozygous state typically shows a less pronounced effect than the homozygous state.
This genotype is found in a significant portion of the population, with frequencies varying by ancestry.
Associated with tooth eruption timing
This genotype corresponds to the variant previously identified in genome-wide association studies as being linked to a reduction in the number of permanent teeth erupted between the ages of 6 and 14. While this association has been observed in large cohorts, it is a statistical trend and does not determine individual dental outcomes, which are influenced by many genetic and environmental factors.
This genotype is common, with the minor allele frequency reported at approximately 0.42 in some major population databases.
What is rs2281845?
A single nucleotide polymorphism, or SNP, is a variation at a single position in a DNA sequence among individuals. The variant rs2281845 is located on chromosome 1q32.1. It is situated in an intergenic region, approximately 250 base pairs upstream of the CACNA1S gene, which encodes a voltage-dependent calcium channel. The genomic region surrounding this SNP also includes the TMEM9 gene, which is involved in transmembrane protein activity. Because this SNP is located in a non-coding region, it does not directly alter the protein sequence of nearby genes. Instead, researchers study such variants to understand how they might influence gene expression or regulatory processes that contribute to complex biological traits, such as the developmental timing of physical growth milestones.
Research and Evidence
The association between rs2281845 and dental development was highlighted in a 2011 genome-wide association study (GWAS) involving over 5,000 women from the Danish National Birth Cohort. The study examined the number of permanent teeth erupted in children between the ages of 6 and 14. Researchers found that the T allele was statistically associated with a reduction in the number of erupted permanent teeth during this developmental window. The evidence for this association is considered moderate, as it stems from large-scale statistical correlations rather than a direct, singular cause-and-effect mechanism. It is important to note that tooth eruption is a complex, multifactorial process influenced by both genetic and environmental factors. While this SNP provides a window into the genetic architecture of dental development, it is only one of many factors that determine the timing of tooth eruption.
Interpreting the Findings
When interpreting genetic data, it is crucial to distinguish between statistical associations and clinical diagnoses. The findings regarding rs2281845 describe population-level trends observed in research cohorts; they do not predict the specific dental development of any individual child. Because the effect size of this variant is relatively small, it does not serve as a diagnostic tool for dental health or developmental delays. Parents or individuals concerned about the timing of permanent tooth eruption should consult a pediatric dentist or an orthodontist. These professionals can provide clinical evaluations based on physical examinations and dental imaging, which are far more accurate for assessing individual development than genetic testing. Genetic information should be viewed as a tool for scientific understanding rather than a substitute for professional medical or dental advice.
How common is this variant?
The frequency of the rs2281845 alleles varies across different ancestral populations. According to global genomic databases, the minor allele frequency is approximately 0.42, though this can fluctuate significantly depending on the specific population group studied.
Frequently asked questions
Does rs2281845 cause missing teeth?
No, this variant is associated with the timing of tooth eruption, not the total absence of teeth. It relates to how quickly permanent teeth emerge during childhood, not whether they develop at all.
Should I get my child tested for this SNP?
There is no clinical utility in testing for this SNP. Dental development is best assessed by a dentist through clinical examination and X-rays, which provide actionable information for your child's care.
Is this variant linked to other health conditions?
The region near rs2281845 is near the CACNA1S gene, which has been studied in the context of conditions like periodic paralysis. However, rs2281845 itself is primarily studied for its association with dental eruption timing.
Can I change my child's tooth eruption timing?
Tooth eruption is a natural biological process. If you are concerned about your child's dental development, consult a pediatric dentist who can determine if any intervention is necessary based on clinical standards.
Sources & further reading
Educational information only, last refreshed 9/17/2026. Not medical advice — these associations describe population statistics, not individual predictions.
Curious what your genotype is for rs2281845?
Upload a raw DNA file from 23andMe, AncestryDNA, MyHeritage, or FamilyTreeDNA and see this variant — plus thousands more — interpreted in your full report.
Get my report — $29Related variants
This variant is significantly associated with increased risk of obstructive sleep apnea and higher apnea-hypopnea index scores in men.
This variant is linked to the presence of hallucinations in patients with Parkinson's disease, suggesting a role in glymphatic system-related sleep disturbances.
This variant is associated with a decreased risk of obstructive sleep apnea in male populations.
This common variant is associated with seasonal affective disorder when triggered by disrupted sleep-wake cycles.
The AA genotype of this variant is associated with a lower risk of developing REM sleep behavior disorder symptoms in patients with Parkinson's disease.
This SNP in the TFCP2L1 gene was identified as a novel genome-wide significant marker for Behcet's disease, a vision-threatening form of uveitis.