What you carry at this position in your DNA and what research says about it.
Height and Growth: 9/10 evidence, 33 publications.
You're viewing every possible genotype for this variant.
None of these is your result. Use the genotype toggle to compare them, then sign up and upload your DNA to see which one is yours.
Sample genotype (not yours): C/C
Slightly Taller Stature and Typical Metabolic Risk
Carrying two copies of the C allele is associated with being about 0.8 centimeters taller than average. This genotype is also linked to typical blood pressure and typical risk of type 2 diabetes.
What this genotype means: Slightly taller stature; Typical metabolic risk profile.
Sample genotype (not yours): C/T
Slightly Taller Stature and Minor Metabolic Risks
Carrying one copy of the C allele is associated with being about 0.4 centimeters taller than average. This genotype also carries a very slight increase in the risk of type 2 diabetes and higher blood pressure.
What this genotype means: Slightly taller stature; Minor increase in metabolic risks.
Sample genotype (not yours): T/T
Typical Stature and Slightly Higher Metabolic Risks
Carrying two copies of the T allele is associated with average height and a very slight increase in the risk of type 2 diabetes. This genotype is also linked to slightly higher systolic blood pressure.
What this genotype means: Typical stature; Slightly higher risk of type 2 diabetes.
Gene function and biological role
Gene Function: HMGA2 encodes a protein that belongs to the non-histone chromosomal high-mobility group protein family [1]. This protein functions as an architectural transcription factor, altering chromatin structure to regulate gene expression during embryonic development [1] [2]. It is highly active during prenatal development and plays a critical role in cell growth and differentiation [2]. Rare, severe mutations in this gene are known to cause dramatic changes in body size in both humans and mice [1] [3]. In adults, its expression is generally low, but it remains a key regulator of overall stature and skeletal growth [3] [4].
Variant Impact: The rs1042725 variant is located in the 3 prime untranslated region of the HMGA2 gene, a region critical for regulating gene stability and expression [1]. This genetic change is one of the most widely replicated genetic markers associated with human height [1] [3]. The C allele is associated with increased expression of HMGA2 during development, promoting greater cellular proliferation and skeletal growth [2]. Conversely, the T allele is linked to slightly lower expression, resulting in a more typical or shorter stature [1] [5]. Beyond height, this regulatory variant has subtle downstream effects on birth weight, head circumference, and metabolic traits [6] [7].
Key Insight: This variant was the very first consistently replicated genetic marker discovered to influence human height in the general population.
Location: HMGA2. Chromosome 12 · 12q14.3 · 66.0 Mb
Estimated prevalence by population
Global 26.7%; European 25.9%; African 38.0%; East Asian 3.6%; South Asian 10.5%; Americas 17.0%; Ashkenazi 11.8%; Finnish 26.3%; Middle Eastern 19.6%; Amish 22.2%.
Estimated CC genotype frequency.
Global 48.1%; European 50.0%; African 47.3%; East Asian 30.7%; South Asian 43.8%; Americas 48.5%; Ashkenazi 45.1%; Finnish 50.0%; Middle Eastern 49.3%; Amish 49.8%.
Estimated CT genotype frequency.
Global 25.2%; European 24.1%; African 14.7%; East Asian 65.7%; South Asian 45.8%; Americas 34.5%; Ashkenazi 43.1%; Finnish 23.8%; Middle Eastern 31.1%; Amish 27.9%.
Estimated TT genotype frequency.
Showing effects for C/C genotype
Lifestyle, Fitness & Aging
Height & Body Size
Height. Evidence: 9/10. Source: PMID 17767157. ~0.8 cm Taller.
Head Circumference. Evidence: 8/10. Source: PMID 22504419. Slightly Larger.
Cardiovascular & Metabolic
Diabetes & Glycemic Traits
Type 2 Diabetes. Evidence: 6/10. Source: PMID 30297969. Typical Risk.
Hypertension
Systolic Blood Pressure. Evidence: 6/10. Source: PMID 35762941. Typical.
Blood Cell & Iron Traits
White Blood Cell Count. Evidence: 8/10. Source: PMID 30595370. Typical.
Endocrine & Reproductive
Pregnancy & Birth Complications
Birth Weight. Evidence: 8/10. Source: PMID 23202124. Slightly Higher.
Showing effects for C/T genotype
Height. Evidence: 9/10. Source: PMID 17767157. ~0.4 cm Taller.
Type 2 Diabetes. Evidence: 6/10. Source: PMID 30297969. Slightly Higher Risk.
Systolic Blood Pressure. Evidence: 6/10. Source: PMID 35762941. Slightly Higher.
White Blood Cell Count. Evidence: 8/10. Source: PMID 30595370. Slightly Higher.
Showing effects for T/T genotype
Height. Evidence: 9/10. Source: PMID 17767157. Typical Height.
Head Circumference. Evidence: 8/10. Source: PMID 22504419. Typical.
Type 2 Diabetes. Evidence: 6/10. Source: PMID 30297969. ~1.05x Higher Risk.
Birth Weight. Evidence: 8/10. Source: PMID 23202124. Typical.
What this genotype means for the people who carry it
Sample genotype: CC (Homozygous)
This genotype is strongly associated with increased height in both children and adults, adding approximately 0.8 centimeters to average stature [1]. The C allele increases the activity of the HMGA2 gene during embryonic development, which promotes skeletal growth and cellular division [2]. This growth-promoting effect is also reflected in early life, as individuals with this genotype tend to have slightly higher birth weights and larger infant head circumferences [3] [4]. In addition to physical stature, carrying two copies of the C allele is associated with a typical or slightly lower risk of developing type 2 diabetes compared to T allele carriers [5]. It is also linked to typical systolic blood pressure and lower neutrophil counts [6] [7]. Overall, this genotype represents a common genetic variation that gently nudges growth and metabolic baselines [1].
Slightly taller stature; Typical metabolic risk profile.
Sample genotype: CT (Heterozygous)
Having one copy of each allele represents an intermediate physical and metabolic profile [1]. Individuals with this genotype are typically about 0.4 centimeters taller than those with the TT genotype [1]. This is due to a moderate level of HMGA2 gene expression during early skeletal development [2]. This intermediate growth effect is also observed in infant head circumference and birth weight, which tend to be slightly above the baseline [3] [4]. On the metabolic side, carrying one T allele introduces a very minor increase in the risk of developing type 2 diabetes [5]. It is also associated with a slight upward trend in systolic blood pressure and white blood cell counts [6] [7]. These subtle variations are highly common and generally have a minimal impact on daily health [1].
Slightly taller stature; Minor increase in metabolic risks.
Sample genotype: TT (Homozygous)
This genotype is associated with a baseline or average height, lacking the growth-promoting effects of the C allele [1]. During development, the T allele is linked to lower expression of the HMGA2 gene, resulting in typical skeletal growth [2]. This is also reflected in early childhood, with typical birth weight and infant head circumference measurements [3] [4]. However, carrying two copies of the T allele is associated with a slightly higher risk of developing type 2 diabetes, with an odds ratio of approximately 1.05 [5]. It is also linked to slightly higher systolic blood pressure and elevated white blood cell counts [6] [7]. These metabolic and physical differences are small and represent normal variation within the human population [1].
Typical stature; Slightly higher risk of type 2 diabetes.
Variants with shared genetic architecture
rs8756 · HMGA2 Gene · Chr 12 · Height and Development
rs1351394 · HMGA2 Gene · Chr 12 · Adult Height and Growth
rs11205277 · SF3B4 Gene · Chr 1 · Adult Height
A common variant of HMGA2 is associated with adult and childhood height in the general population.
HMGA2 is confirmed to be associated with human adult height.
Common variants at 12q15 and 12q24 are associated with infant head circumference.
High Blood Pressure and Intraocular Pressure: A Mendelian Randomization Study.
Leveraging Polygenic Functional Enrichment to Improve GWAS Power.
Content updated August 2026.
ReadYourDNA provides educational interpretation of DNA data you already have. It is not diagnostic, not a substitute for professional medical advice, diagnosis, or treatment, and is not intended to diagnose, treat, cure, or prevent any disease. Talk to a clinician before acting on any result.
Raw DNA Data Reports for 23andMe & AncestryDNA · About ReadYourDNA · FAQ · Methodology & Science · Pricing · Support and complaints · Legal & Contact · Health Traits · Pharmacogenomics · Carrier Status · Variant Explorer · The Human Karyotype · Privacy Policy · Terms of Service · Accessibility · Consumer Health Data Privacy · Your Privacy Choices · Editorial Standards · Your Data, Checkable · Sample Report · ReadYourDNA and Promethease compared · What is inside a 23andMe raw data file · What is inside an AncestryDNA raw data file · What a chatbot can and cannot do with your raw DNA file · Where a raw DNA file can still be uploaded in 2026
Written, maintained and operated by Martin Pechhacker, sole proprietor, Vienna, Austria. Trade register GISA 40064420. support@readyourdna.com