Why are genetic disorder caused by abnormal number of chromosomes?
Some chromosomal conditions are caused by changes in the number of chromosomes. These changes are not inherited, but occur as random events during the formation of reproductive cells (eggs and sperm). An error in cell division called nondisjunction results in reproductive cells with an abnormal number of chromosomes.
What are some disorders caused by nondisjunction of autosomes?
Nondisjunction causes errors in chromosome number, such as trisomy 21 (Down syndrome) and monosomy X (Turner syndrome). It is also a common cause of early spontaneous abortions.
What type of disorder is caused because of abnormalities in genes Class 12?
Genetic disorders arising due to mutation in the chromosome are chromosomal disorders. Alteration in the number and functioning of the chromosomes leads to chromosomal disorders. A chromosomal disorder affects many genes at a time and can be fatal.
What type of disorder is caused because of abnormalities in genes?
Chromosomal disorders, where chromosomes (or parts of chromosomes) are missing or changed. Chromosomes are the structures that hold our genes. Down syndrome is a chromosomal disorder. Complex disorders, where there are mutations in two or more genes.
What is autosomal abnormality?
“Autosomal” means that the defective gene is located on any of the chromosomes that are not the sex chromosomes (X or Y). If one parent has the gene, each child of the couple has a 50 percent chance of inheriting the disorder. An example of an autosomal dominant disorder is Huntington disease.
What is genetic disorder Class 9?
A genetic disorder is a health problem caused by one or more abnormalities in the genome. It can be caused by a mutation in a single gene (monogenic) or multiple genes (polygenic) or by a chromosomal abnormality.