Carrier
From The School of Biomedical Sciences Wiki
A carrier is an organism that carries a disease without showing any symptoms. If the disease is genetic, the carrier will be heterozygous, with a dominant, healthy allele and a reccessive allele for the disease state. In the event of two carriers mating, there is a 25% chance their offspring will be affected by the disease, 50% chance of the offspring being carriers or a 25% chance of the offspring being healthy and not a carrier[1].
An example of this is Cystic Fibrosis, where 1 in 25 of the white population are carriers of the CF gene, showing no signs of having CF themselves.
A Punnett Square showing two carriers mating: (H is healthy, dominant allele, he is recessive for disease state) indicates how alleles from each parent cross.
H | h | |
H | HH | Hh |
h | Hh | hh |
References
- ↑ D.L. Hartl, E.W.Jones.(2000)Genetics: analysis of genes and genomes, 5th edition. Sudbury, Jones and Bartlett publishers