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NCBI database of genetic variation.
The loss of genetic material, ranging from a single nucleotide to an entire chromosome.
A genetic alteration which arises in an individual that was not inherited from a parent, or was present for the first time in the egg or sperm from the parent.
The number of sequencing reads generated during massively parallel sequencing which align to and cover a specific genomic region or base pair. Higher depth of coverage generally increases confidence in variant calls.
Twins that developed from two separate fertilized eggs.
A characteristic, trait, or disorder which is phenotypically expressed when only one variant allele is present.
A mutation which results in an altered protein which interferes with the normal wild-type protein product, and may result in a novel protein function. These types of mutations may be more deleterious than a mutation which results in a premature stop or null allele when polymeric molecules are involved.
When an individual is heterozygous at two different loci (which results in a disease).
An additional copy (gain) of genetic material, ranging from a single nucleotide to an entire chromosome.
See dizygotic twins.