Home | | Pathology | Mendelian Disorders

Mendelian Disorders - | Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail |

Chapter: Pathology: Genetic Disorders

Mendelian Disorders

Mendelian disorders are characterized by single gene mutations.

MENDELIAN DISORDERS

Mendelian disorders are characterized by single gene mutations. Common types ofmutations include point mutations and frameshift mutations.

·            Point mutations occur with a single nucleotide base substitution, which mayproduce a variety of effects. The form of point mutation called synonymous mutation (silent mutation) occurs when a base substitution results in a codon that codes for the same amino acid. The form of point mutation called mis-sense mutation occurs when a base substitution results in a new codon and a change in amino acids. The form of point mutation called a nonsense mutation occurs when a base substitution produces a stop codon and therefore produces a truncated protein.

 

·            Frameshift mutations occur when insertion or deletion of bases leads to ashift in the reading frame of the gene.

 

The location of a mutation will alter its potential effects. Mutations involving coding regions of DNA may result in abnormal amino acid sequences; decreased production of the protein; truncated or abnormally folded protein; or altered or lost function of the protein. Mutations of promoter or enhancer regions may interfere with tran-scription factors, resulting in decreased transcription of the gene.

Patterns of inheritance for genetic diseases show wide variation, and the genetic pattern of a disease may be classified as autosomal dominant; autosomal recessive; X-linked recessive; X-linked dominant; triplet repeat mutations; genomic imprint-ing; mitochondrial; or multifactorial.



Study Material, Lecturing Notes, Assignment, Reference, Wiki description explanation, brief detail


Privacy Policy, Terms and Conditions, DMCA Policy and Compliant

Copyright © 2018-2023 BrainKart.com; All Rights Reserved S21. Developed by Therithal info, Chennai.