Inheritance Autosomal Recessive

Autosomal recessive inheritance is the inheritance of a trait controlled by recessive alleles of an autosomal gene.

With autosomal recessive inheritance, the pathological trait manifests itself only in the homozygous state for the recessive allele. This means that the disease will develop if a child inherits one recessive allele from each parent.

The parents of a sick child are usually healthy, since they are carriers of only one recessive allele. However, the probability of such a couple having a sick child is 25%, since with each pregnancy there is a 25% chance that the fetus will inherit a recessive allele from each parent.

Examples of diseases with an autosomal recessive type of inheritance are phenylketonuria, cystic fibrosis, albinism, sickle cell anemia, etc. To identify carriage of such diseases, it is important to conduct medical genetic counseling.

Autosomal inheritance is recessive

**Brief definition.** Hereditary traits caused by a recessive allele of a gene. These characteristics are usually signs of polymorphism and are not manifested in most cases, but can be expressed in homozygotes for a recessive allele.

The presence of such a trait indicates the recessive nature of its transmission. In a genotype, a recessive gene is designated by the index r, a dominant gene by D, and normal (they are called epistatic) genes by E. Then recording the genotype makes it possible to determine the phenotype using the formula: DEd / ddee,