Genetic disorder occurrence

Question

Describe how genetic disorders occur?

Answer 1

Genetic disorders are congenital, meaning they are something you are born with, not something you obtain throughout life. These disorders are called mutations. Genetic mutations occur when the nucleic acids transferring DNA become out of order for some reason. There are several types of genetic mutations- some are silent (not seen) and some create larger issues for the organism. The mutations that cause issues are what develop disorders.

Answer 2

I would add to the answer of Julia that those genetic disorders occurs generally by heredity. The specific mutations occurred at the DNA of an ancestor and are inherited through generations through the gametes.

Answer 3

Genetic disorders can occur in a variety of ways. Most commonly, they are the result of altered DNA sequence: a change in the genetic "blueprint," which can be as small as a single nucleotide change: changing one base for another, i.e changing an A for a G, for example.This can cause either a missense mutation: a change from one amino acid to another that alters the protein of the gene or a nonsense mutation which changes a codon of a gene to a premature STOP codon. Or, as large as major genomic alterations such as Inversions: flipping of segments of DNA or Translocations: putting segments of DNA in different areas within the genome. Other ways genetic disorders can arise are through Indels (Insertions or Deletions) of DNA which can change the reading frame of the gene, which can completely alter the protein product of the gene.

Mutations may also occur not from just changing the genetic blueprint but also through change in copy number: a change in the amount of DNA present. If, for example, there was a non-disjunction event during Meiosis I or II, the resulting gamete may have an extra copy of a chromosome, such as chromosome 21, which can cause Trisomy 21 or Down syndrome.