Autosomal recessive Disorders

Autosomal recessive conditions are genetic disorders caused by mutations in both copies of a gene located on one of the 22 autosomal chromosomes, affecting males and females equally. These mutations can be either homozygous, where both copies of the gene have the same pathogenic variant, or compound heterozygous, where each copy of the gene has a different pathogenic variant. Genes serve as the blueprint for all bodily functions and structures, directing growth and development. However, certain variations in these genes can lead to malfunctions or harmful alterations in their function, known as pathogenic variants.

In the context of autosomal recessive inheritance, a condition manifests when an individual inherits two recessive variants, one from each parent, for the same gene. These parents, who each carry one pathogenic variant and one normal variant of the gene, are referred to as carriers. They typically do not show symptoms of the condition because they have one working copy of the gene. However, when both parents are carriers, there is a 25% chance with each pregnancy for the child to inherit both pathogenic variants, one from each parent, leading to the expression of the autosomal recessive condition.

Let us review some key terms to understand...