Can AS Marry AS, All You Need To Know About Genotype

Genotype is integral to human genetics since it determines various health aspects, including the likelihood of inheriting genetic illnesses. In particular, genotype compatibility is essential in determining the chance of passing genetic disorders to biological children. 

Genotype is an individual’s genetic composition, determined by the mix of alleles acquired from their biological parents. Alleles are variations of a gene that can code for a variety of phenotypes.

Each inherits two copies of each gene, one from each parent, resulting in three genotypes for a given gene: homozygous dominant (AA), heterozygous (AS), or homozygous recessive (SS).

• AA: Individuals with two normal haemoglobin genes have the AA genotype, which does not have the sickle cell gene. They are thought to have normal haemoglobin and are not at risk of having sickle cell disease.
• AS: People with one normal haemoglobin gene and one sickle cell gene have the AS genotype; while they carry the sickle cell trait and do not often exhibit sickle cell disease symptoms, they can pass on the sickle cell gene to their offspring.
• SS: Individuals with two sickle cell genes have the SS genotype and are susceptible to sickle cell disease. Symptoms include persistent pain, exhaustion, anaemia, and increased infection susceptibility.

When two people with the AS genotype marry and have children, their offspring may acquire both parents’ sickle cell genes, resulting in the SS genotype and sickle cell disease (SCD). The chances of having a kid with SCD in an AS-AS union are as follows:

• 25% likelihood of producing a child with the AA genotype (normal haemoglobin).
• Fifty per cent risk of producing a child with the AS genotype (carrier of the sickle cell trait).
• 25% likelihood of having a child with the SS genotype (affected by sickle cell disease).

Marrying someone with the same AS genotype is risky and is not advisable, especially for those who were not aware of their carrier status or did not receive genetic counselling. This action might have severe consequences for the couple and their future offspring.

This is because genetic counselling is critical in informing people and couples about their hereditary risks, such as the consequences of AS-AS marriage and the likelihood of producing children with SCD. 

Risk Involved in AS-AS Marriage

• The biggest issue with AS-AS marriage is an increased likelihood of having children with SCD, a chronic and potentially fatal disorder characterized by discomfort, organ damage, and decreased life expectancy.
• Caring for a child with SCD can pose a substantial emotional and financial burden on families, including numerous physician appointments, hospitalizations, and specialized care needs.
• Parents of children with SCD may face shame, anxiety, and stress as a result of their child’s medical condition. SCD can also impact the affected individuals’ quality of life and social connections.
• Family Planning Issues: Couples who learn their AS genotype status after marriage may have difficulties with family planning and decision-making, including but not limited to concern about future pregnancies and the risk of passing down SCD to their children.

AS marrying AS is a perilous and life-changing decision. While people with the AS genotype seldom have sickle cell disease symptoms, marrying someone with the same genotype increases the probability of having SCD offspring.

Individuals and couples who seek genetic counselling and testing can make informed decisions about their reproductive health and make efforts to prevent the spread of SCD to future generations.

Study the chart below for a clearer understanding of genotype compatibility:

AA + AA = AA, AA, AA, AA (Recommended)

AA + AS = AA, AS, AA, AS, (Recommended)

AA + SS = AS, AS, AS, AS, (Recommended, seek counselling)

AA + AC = AA, AA, AA, AC. (Recommended)

AS + AS = AA, AS, AS, SS, (Not recommended, seek counselling)

AS + SS = AS, SS, SS, SS, (Not recommended, seek counselling)

AS + AC = AA,  AC, AS, SS. (Not recommended; seek counselling)

SS + SS = SS, SS, SS, SS, (Not recommended, seek counselling)

AC + SS = AS, AS, SS, SS, (Not recommended, seek counselling)

AC + AC = AA, AC, AC, SS. (Not recommended, seek counselling)