HBA1 rs35723200: What Your Genotype Means
The rs35723200 variant is a rare genetic change located in the HBA1 gene, which provides instructions for making a component of hemoglobin. This specific variant is associated with rare hemoglobinopathies, such as Hemoglobin Rouen and Hemoglobin Ethiopia, which can influence blood health and pregnancy outcomes.
What each genotype means
Typical hemoglobin profile
This genotype represents the reference sequence for the HBA1 gene at this position. It is not associated with the hemoglobin variants known to cause hemoglobinopathies like Hemoglobin Rouen or Hemoglobin Ethiopia.
This is the most common genotype observed in the general population.
Potential hemoglobin variant carrier
Carrying one copy of the C allele at this position is associated with the presence of specific hemoglobin variants, such as Hemoglobin Rouen or Hemoglobin Ethiopia. Because this variant is rare, you should discuss these findings with a genetic counselor or hematologist to understand if this has any clinical relevance for your health or reproductive planning.
This genotype is rare in the general population.
Hemoglobin variant associated
This genotype indicates the presence of the C allele on both chromosomes, which has been linked to hemoglobinopathies including Hemoglobin Rouen and Hemoglobin Ethiopia. As these conditions can impact red blood cell function, it is recommended to consult with a healthcare provider to discuss potential clinical implications and appropriate follow-up testing.
This genotype is extremely rare in the general population.
Understanding the rs35723200 Variant
The rs35723200 variant is a single nucleotide polymorphism (SNP) located on chromosome 16 within the HBA1 gene. In genetic terms, this variant represents a specific change in the DNA sequence at a precise location. The HBA1 gene is part of a cluster on chromosome 16 that is essential for the production of alpha-globin, a protein subunit that combines with other components to form hemoglobin. Hemoglobin is the vital protein in red blood cells responsible for transporting oxygen throughout the body. Because this variant occurs in a gene critical for blood function, researchers monitor it closely to understand how it might alter the structure or stability of the hemoglobin molecule, potentially leading to clinical conditions known as hemoglobinopathies.
The Role of the HBA1 Gene
The HBA1 gene encodes the alpha-globin protein. Humans typically have two copies of the HBA1 gene and two copies of the HBA2 gene, which together ensure the body produces enough alpha-globin to form functional hemoglobin tetramers. These genes are highly similar, and their coordinated expression is necessary for healthy red blood cell function. When a variant like rs35723200 occurs, it can lead to the production of an altered alpha-globin chain. Depending on the nature of the change, this can result in hemoglobin that is unstable or has an altered affinity for oxygen. Such changes are the underlying cause of various hemoglobinopathies, which can range from mild, asymptomatic conditions to more severe forms of anemia that may require medical management.
Research and Clinical Associations
Scientific literature associates rs35723200 with specific hemoglobin variants, including Hemoglobin Rouen and Hemoglobin Ethiopia. These conditions are characterized by structural changes in the alpha-globin chain, such as the substitution of tyrosine with histidine at position 140. Research indicates that these alterations can lead to a moderate increase in oxygen affinity or instability of the hemoglobin molecule. In the context of reproductive health, hemoglobinopathies are significant because they can impact the oxygen-carrying capacity of the blood during pregnancy, a time when the body's demand for oxygen increases. While the evidence linking this specific SNP to clinical outcomes is considered moderate, it is categorized as a variant of interest in reproductive genetic screening because of its potential to influence maternal and fetal health.
Population Frequency and Prevalence
The rs35723200 variant is classified as rare in the general population. Because it is not a common polymorphism, it is not typically found in the majority of individuals. Genetic databases often show very low or absent allele frequencies across diverse ancestral groups. This rarity means that most people will not carry this variant. When it is identified, it is usually through targeted clinical testing rather than routine population screening. Because the frequency is so low, large-scale population studies have limited data on its distribution, and the clinical impact is often studied in the context of specific families or individuals who present with unexplained hematological findings.
Navigating Genetic Information
If you have received information about the rs35723200 variant, it is important to understand that this is a specialized finding. Genetic variants in the HBA1 gene can have varying clinical implications, and the presence of a variant does not automatically imply a severe health condition. You cannot use this information to diagnose yourself or predict specific health outcomes without professional guidance. If you are concerned about reproductive health or potential hemoglobinopathies, the most appropriate step is to consult with a genetic counselor or a hematologist. These professionals can interpret your results in the context of your overall health, family history, and other clinical tests. Always discuss any medical concerns or potential implications for pregnancy with your healthcare provider before making decisions about your health.
How common is this variant?
The rs35723200 variant is rare across all major ancestral populations, with very low allele frequencies reported in global genetic databases.
Frequently asked questions
What is a hemoglobinopathy?
A hemoglobinopathy is a group of genetic disorders that affect the structure or production of hemoglobin, the protein in red blood cells that carries oxygen. These conditions can lead to anemia or other blood-related health issues.
Is rs35723200 the same as alpha-thalassemia?
While rs35723200 is located in the HBA1 gene, it is a specific variant associated with structural hemoglobin changes rather than the gene deletions typically responsible for alpha-thalassemia. However, both can affect hemoglobin function.
Should I be worried if I have this variant?
The presence of a variant does not necessarily mean you have a disease. You should discuss your specific genetic report with a healthcare provider or genetic counselor who can provide context based on your personal and family health history.
How is this variant detected?
This variant is typically detected through specialized genetic testing, such as sequencing of the HBA1 and HBA2 genes. It is not usually included in standard, broad-spectrum ancestry or wellness genetic tests.
Sources & further reading
Educational information only, last refreshed 10/2/2026. Not medical advice — these associations describe population statistics, not individual predictions.
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