Autosomal recessive inheritance
Two alleles have to be mutated and inactivated to manifest (mark, notice) the disease. Homozygous for the relevant gene.Affected children have carrier parents. Two heterozygous carrier parents can have an affected, carrier or normal offspring. The affected progeny could be both male and female. This autosomal recessive inheritance often results from loss of function of an essential gene product.
The full grown disease is not expected to be seen in the second generation but only if both partners are carriers for the mutation it will be seen. If the parents were not carriers but one was a carrier, we would see affected individuals after the second generation
An individual that lacks pigmentation in skin, hair and eyes is known to have Albinism. Individuals lacking an important enzyme that is needed to convert the amino acid phenylalanine into tyrosine have an autosomal recessive trait known as Phenylketonuria. By lacking this enzyme the phenylalanine along with its by-product phenylpyruvate accumulate to toxic levels in the blood. These toxic levels can cause mental retardation in the individual. A way in which to cure this PKU condition is to treat the individual if it is a new born with a special diet that is low in phenylalanine.
Screening of newborns and fetuses for serious inherited diseases, Tests for identifying carriers, and Genetic counselling.
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