If you inherit two copies of every gene, one from each parent, how do your cells know which version to use?
- Alleles, alternative forms of genes, can be dominant or recessive.
- Dominant alleles will always be expressed even if only one copy is present.
- Recessive alleles will only be expressed if both copies are present.
- Cystic Fibrosis is a genetic condition caused by a recessive gene. Huntington's Disease is a condition caused by a dominant allele.