Types of Mendelian Disorders
Depending on the pattern of inheritance, Mendelian disorders can be classified into five different types. These are:
- Autosomal Dominant Disorder: These disorders occur when a mutation occurs in a gene located on an autosomal chromosome. These traits are dominant and are expressed even if only one copy of the mutated gene is present on the loci.
- Autosomal Recessive Disorders: These disorders also occur when the mutation occurs in an autosomal gene. However, these are recessive disorders and are expressed in an individual only when two copies of mutated genes are present on the loci. Typically both parents are carriers of the mutated gene but do not show symptoms of the disorder.
- Sex-linked Dominant Disorders: These disorders are caused by mutations in genes located on the sex chromosomes (X and Y). If a dominant allele is present on the X chromosome, females are more likely to be affected than males because they have two X chromosomes.
- Sex-linked Recessive Disorder: These disorders are caused by mutations in genes located on the sex chromosomes (X and Y). Since males have only one X chromosome, they are more likely to be affected if they inherit a mutated X-linked recessive gene.
- Mitochondrial Disorders: These disorders are caused by mutations in the mitochondrial DNA, which is separate from the nuclear DNA and is inherited exclusively from the mother.
Also Read: Autosomal Dominant Inheritance
Types of Mendelian Disorders in Humans and Examples
Mendelian disorders in humans are genetic conditions that follow Mendel’s laws of inheritance, resulting from mutations in a single gene. Common examples of Mendelian disorders are hemophilia, cystic fibrosis, thalassemia, etc. These disorders adhere to predictable patterns of transmission, either through autosomal dominant, autosomal recessive, or X-linked inheritance.
Understanding these Mendelian disorders in humans helps us understand the relationship between genes and phenotypes and guides medical research to promote health and prevent disease. In this article, we will study Mendelian Disorder, the Principles of Mendelian Disorders, and the examples of Mendelian Disorder in detail.
Table of Content
- Mendelian Disorders
- Principles of Mendelian Disorders
- Types of Mendelian Disorders
- Examples of Mendelian Disorders in Humans
- Conclusion
- FAQs on Mendelian Disorders in Humans