What is the difference between allelic heterogeneity and locus heterogeneity?
Allelic heterogeneity occurs when different variants at a single gene locus cause the same or similar phenotypic expressions of a disease or condition. Locus heterogeneity occurs when variants at different gene loci cause the same or similar phenotypic expressions of a disease or condition.
What is the difference between heterozygous and compound heterozygous?
A mutation affecting only one allele is called heterozygous. A homozygous mutation is the presence of the identical mutation on both alleles of a specific gene. However, when both alleles of a gene harbor mutations, but the mutations are different, these mutations are called compound heterozygous.
Is genetic heterogeneity the same as locus heterogeneity?
There are two types of genetic heterogeneity: allelic heterogeneity, which occurs when a similar phenotype is produced by different alleles within the same gene; and locus heterogeneity, which occurs when a similar phenotype is produced by mutations at different loci.
How does allelic heterogeneity work?
Allelic heterogeneity occurs when two or more alleles of a single locus are independently associated with the same trait, while locus heterogeneity occurs when two or more DNA sequence variations at distinct loci are independently associated with the same trait.
Are compound heterozygotes carriers?
Autosomal Recessive Inheritance If each copy of the gene has a different deleterious mutation, the defect is termed compound heterozygous. Each parent of an affected patient is typically a heterozygous carrier, and has one normal and one abnormal copy of the gene (Figure 3.1B).
What causes allelic heterogeneity?
Allelic heterogeneity is the phenomenon in which different mutations at the same locus lead to the same or very similar phenotypes. These allelic variations can arise as a result of natural selection processes, as a result of exogenous mutagens, genetic drift, or genetic migration.
What is the difference between mutational heterogeneity and locus heterogeneity?
Allelic heterogeneity refers to instances where mutations in different alleles at the same locus produce the same disease. By contrast, locus heterogeneity describes mutations in different genes whereby any one mutation generates the same disorder (Figure 1; McClellan and King, 2010).
What is the difference between locus and allele?
Alleles are variants of the same gene that occur on the same place on a chromosome. A locus refers to the location on the chromosome where the gene is found. Loci is the plural form of locus.
Is cystic fibrosis locus heterogeneity?
Allelic heterogeneity describes the ability of different mutations within the same gene to cause the same disease (B). Cystic fibrosis is used to demonstrate this form of heterogeneity, with as many as 1,500 CFTR mutations being attributed to causing the disorder (O’Sullivan and Freedman, 2009).
What is the difference between allelic and Locus heterogeneity?
There are two types of genetic heterogeneity as allelic and locus heterogeneity. Allelic heterogeneity describes the ability of different mutations within the same gene (different alleles at a locus) to produce variable expression of a condition, especially a disease.
Which is the best description of compound heterozygosity?
Compound heterozygosity. In medical genetics, compound heterozygosity is the condition of having two or more heterogeneous recessive alleles at a particular locus that can cause genetic disease in a heterozygous state; that is, an organism is a compound heterozygote when it has two recessive alleles for the same gene,
When do you have two dominant alleles you are a heterozygote?
If an individual has two dissimilar alleles (one dominant and one recessive (Aa)) for a locus, we call it heterozygote. The condition of having two different alleles for a gene is called heterozygous state. Compound heterozygote and double heterozygote are two types of heterozygous situations.
What are the two types of genetic heterogeneity?
Mutations in different loci of the same gene or mutations in different genes can produce genetic heterogeneity. There are two types of genetic heterogeneity as allelic and locus heterogeneity.