premutation


Also found in: Medical.

premutation

[‚prē·myü′tā·shən]
(genetics)
A heritable change, such as a trinucleotide repeat expansion, that has no phenotypic effect but greatly increases the likelihood of a further change at the altered site, resulting in a characteristic phenotype.
References in periodicals archive ?
Premutation carriers with repetition of CGG triplets between 55 and 200, are at high risk to develop Fragile X-associated Tremor/Ataxia Syndrome (FXTAS) or Fragile X-associated Primary Ovarian Insufficiency (FXPOI) (8, 9, 10).
The FMR1 (Fragile X) premutation carrier status could be a cause, or presence of 21-hydroxylase and/or adrenal antibodies indicate autoimmune polyglandular syndrome.
The CGG tandem repeat variation length is defined as normal ([less than or equal to]50), premutation (50-200) and full mutation ([greater than or equal to]200 tandem repeats).
Men and women with the premutation are at risk for a number of related symptoms such as ataxia (FXTAS, OMIM #300623) or premature ovarian failure (FXPOI, OMIM #311360).
His heart rate variability test revealed autonomic system involvement toward parasympathetic activity and his genetic test revealed expanded CGG repeat above 60 within the premutation range (55-200) in the fragile X mental retardation I (FMRI)gene.
Expansion of the fragile X CGG repeat in females with premutation or intermediate alleles.
Multiresponse premutation is a nonparametric procedure for testing differences between two or more groups; the advantage of this method is that it does not involve assumptions (such as multivariate normality and homogeneity of variances) that are seldom met with ecological data on community (McCune and Grace, 2002).
For example, not all pan-ethnic panels include analysis for premutation carriers, making it important to inquire about a history of unexplained mental retardation and autism in males, since this may stem from Fragile X syndrome.
For example, it is very important to accurately determine the size of fragile X premutation expansions to correctly predict the risk of allelic expansion, premature ovarian failure, and fragile X-associated tremor/ataxia syndrome.
Participants consisted of students with singing voices in premutation, during mutation, and postmutation vocal stages.
Would you predict that this gene comes from a normal person, a person with a premutation, or a person afflicted with Fragile-X Syndrome?