Autosomal recessive gene

Autosomal recessive gene mutations in which both copies of a gene must be mutated for the trait to become manifest. 

Wolfram syndrome [26] A syndrome of DIDMOAD. While most cases have been ascribed to an autosomal recessive gene mapping to chromosome 4pl6, some cases of early-onset DIDMOAD might result from mtDNA mutations or deletions. 

A review of medical research has led to the conclusion that ethnic differences concerning lactose intolerance are largely genetic in origin. A culture historical hypothesis has been offered to explain the present-day occurrence of various Old World groups with high and low incidences of lactose intolerance based on milk use (Simoons 1981). It is currently believed that the decline in lactase activity with age is determined by an autosomal recessive gene and is not influenced by the amount of lactose consumed. 

Cioli, D., Pica-Mattoccia, L. and Moroni, R. (1992) Schistosoma mansoni hycanthone/oxamniquine resistance is controlled by a single autosomal recessive gene. Experimental Parasitology 75, 425 432. 

In 1955 the appearance of an inherited mammalian muscular dystrophy was reported in mice of the Bar Harbor 129 strain (M9), in which breeding experiments after ovarian transplantation confirmed its transmission by a single mutant autosomal recessive gene (S32). This disease is analogous to, though not necessarily identical with, human muscular... 

This disease is caused by an autosomal recessive gene mutation (localization on chromosome 2) and leads to an enzyme defect in mitochondrial steroid-27 hydroxylase. The enzyme itself is responsible for the breakdown of cholesterol side-chains in bile acid synthesis. Such a defect results in the formation of cholestanol, a reduction product of cholesterol. It is deposited in various organs, particularly in the tendons and in the nervous system, because the substance cannot be broken down adequately. Deposition takes place conjointly with cholesterol. (209, 210)... 

E. Since sickle cell anemia has an autosomal recessive inheritance pattern and the incidence in the United States to persons of African descent is approximately 1/12, then each parent has a 1/12 chance of being a carrier. Since it is an autosomal recessive gene, then their offspring would have a 1/4 chance of being homozygous if both of their parents were also carriers. Thus, the chances of having a child with the sickle cell trait is (l/12)(l/12)(l/4) or 1/576. 

All newborn infants have an increased concentration of copper in the liver, and a decreased concentration of a specific plasma copper-protein, ceruloplasmin, in comparison to individuals over one year of age (1 ). The rare infant who has inherited a pair of the specific autosomal recessive gene that causes Wilson s disease exhibits an excess of hepatic copper and a deficiency of ceruloplasmin for life. 

Thalassemia is a hereditary disease transmitted by an autosomal recessive gene and characterized by the incapacity to form normal adult hemoglobin (A) in sufficient amounts. The disease is best defined as an incapacity of the red cells to achieve normal hemoglobin concentration either because of a block in the synthetic pathway, or because of a defect in the structure of the erythrocyte [28, 29]. 

A simple assay for the serum paraphenylenediamine oxidase present in serum was developed and proved to be useful in the early detection of hepatolenticular degeneration. It is usually advisable to examine all the children of a family in which Wilson s disease is discovered because the disease is apparently transmitted by an autosomal recessive gene and might therefore be manifest with various degrees of severity in several members of the same family. 

The mechanism by which the absence of the dehalogenase leads to low thyroxine levels and cretinism is not clear. Two different theories have been proposed. The first postulates the existence of an additional defect namely, an inability to couple iodotyrosine to form T3 and T4. The second proposes that the absence of dehalogenase leads to a glandular hyperfunction in which hormone precursors are released before they can be used for thyroglobulin biosynthesis. It has now been established that the dehalogenase defect results from the absence of a single autosomal recessive gene. 

A number of factors affect the incidence and establishment of diabetes. The mechanism by which these factors precipitate the appearance of the disease is often unclear. The role of heredity in diabetes is now well established. Observations made on siblings and twins in diabetic families have led to the conclusion that diabetes is transmitted by an autosomal recessive gene. Yet diabetes becomes manifest only in late adolescence and adulthood. Therefore, new physiological or pathological conditions must appear during development to precipitate the expression of the genotype into the phenotype. 

Periodic paralysis is a rare hereditary disease observed in patients of practically any age (the reported cases include patients from 1 to 56 years old). The disease is transmitted by an autosomal recessive gene and is somewhat more common among women than men. Patients with periodic paralysis have attacks of flaccid paralysis, preceded by hypersecretion of aldosterone. Usually there are no changes in adrenocortical histology. 

The hypothesis that human metabolism of isoniazid is controlled by two allelic genes and that the slow inactivator is homozygous for an autosomal recessive gene was reexamined in the light of these data by Evans... 

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