Iowa Institute of Human Genetics

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  • R

    Rare allele:

    At a given locus, the nucleotide seen least frequently in a given population. An allele is considered rare when it has a frequency of less than 1% in a given population.

    Rearrangement:

    A structural alteration of a chromosome which results in an abnormal configuration, such as an inversion or translocation, and may interrupt a gene sequence. Chromosomal rearrangements are typically identified on a karyotype.

    Recessive:

    A characteristic, trait, or disorder which is phenotypically expressed when two variant alleles are present.

    Reference genome:

    The DNA sequence of an organism created from the combined DNA sequences of multiple individuals. It is considered to represent the common genetic information in humans and is a useful to for genetic analyses.

    Resequencing:

    The sequencing of a specific exon or genomic region for the identification of DNA variants. Often performed to screen a large population for a gene of interest, or to confirm a DNA variant identified by massively parallel sequencing.

    RFLP:

    Restriction fragment length polymorphism

    RT-qPCR:

    Reverse transcriptase quantitative PCR