A genetic disorder is a disease caused in whole or in part by a change in the DNA sequence away from the normal sequence.
A genetic disorder is caused by an altered gene or set of genes. The four broad groups of genetic disorders are single gene disorders, chromosome abnormalities, mitochondrial disorders and multifactorial disorders. The four main ways of inheriting an altered gene are autosomal dominant, autosomal recessive, X-linked dominant and X-linked recessive.
Genes are paired – one copy of each gene pair is inherited from the mother and the other copy from the father.
A genetic disorder is caused by an altered gene or set of genes. The four broad groups of genetic disorders are single gene disorders, chromosome abnormalities, mitochondrial disorders and multifactorial disorders. The four main ways of inheriting an altered gene are autosomal dominant, autosomal recessive, X-linked dominant and X-linked recessive.
Genes are paired – one copy of each gene pair is inherited from the mother and the other copy from the father.
A mutation is a permanent change in the sequence of DNA.
Mutations in DNA sequences generally occur through one of two processes.
DNA damage from environmental agents such as ultraviolet light (sunshine), nuclear radiation or certain chemicals
Mistakes that occur when a cell copies its DNA in preparation for cell division.
Mutations can be caused by external (exogenous) or endogenous (native) factors, or they may be caused by errors in the cellular machinery.