Abstract
In genetic situations where two copies (alleles) of a gene are present (i.e., autosomal genes and X-linked genes in females), a 'carrier' has an abnormal (generally mutationally defective) allele at one of the two alleles. This mutant allele usually does not cause an abnormal phenotype and is said to be recessive. However, a carrier may pass the chromosome containing the mutant allele to offspring and when this is combined with a similarly mutant allele from the other parent (for autosomal genes) or is present in an uncomplemented state (an X-linked mutation in a male), the defect caused by the gene will be manifest. A wide variety of gene variations is becoming recognized through genomic sequencing and the carrier state can be detected by several methods.
Original language | English (US) |
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Title of host publication | Brenner's Encyclopedia of Genetics |
Subtitle of host publication | Second Edition |
Publisher | Elsevier Inc. |
Pages | 435-436 |
Number of pages | 2 |
ISBN (Electronic) | 9780080961569 |
ISBN (Print) | 9780123749840 |
DOIs | |
State | Published - Feb 27 2013 |
Keywords
- Allele
- DNA
- Heterozygote
- Homozygote
- Mutation
- Phenotype
- Polymorphism
- Recessive
- Screening
- Selection
- Sequence
ASJC Scopus subject areas
- General Agricultural and Biological Sciences
- General Biochemistry, Genetics and Molecular Biology
- General Medicine