null allele


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Related to null allele: Null mutation

null allele

A segment of DNA which is not known to encode a protein product.

null allele

a form of a gene whose product is either absent at the molecular level, or is present but has no measurable phenotypic function. For example, in a heterozygote with INCOMPLETE DOMINANCE one gene form is a ‘null allele’ and is inactive, while the other allele is unable to compensate for the null allele and so produces an intermediate phenotype.

allele

one of two or more alternative forms of a gene at the same site or locus in each of a pair of chromosomes, which determine alternative characters in inheritance. Called also allelomorph.

blank allele
an allele which produces an antigen which cannot be detected.
null allele
see silent allele (below).
silent allele
one that produces no detectable effect.
References in periodicals archive ?
Furthermore, one locus had relatively high estimate of null allele frequency and Hardy-Weinberg equilibrium was not possible to calculate for other 3 loci.
The molecular basis of a microsatellite null allele from the White Sands pupfish.
A sample of the apparent TPOX null allele carriers who were identified in the way described above were re-profiled using the COfiler or Identifiler kits, which use different primers to those employed in the Powerplex 16 kit.
2007: Inference of population structure using multilocus genotype data: dominant markers and null alleles.
Some of these loci have exhibited strong evidence of null alleles in bowheads.
In the context of a breeding population, the effect of a null allele is to mistakenly reject a true father, due to a lack of observed shared alleles with the offspring; that is, the number of real parents is underestimated.
We note that our sample sizes were small for all 6 populations (N = 10); larger samples of individuals would have provided a more robust estimate of the rate of selling and null allele frequency.
We removed three microsatellite loci (MSMM5, MSMM8, and Moe7) from final analyses because they showed evidence for a null allele.
If evidence was found for a null allele in any sample and locus combination, the frequency of the null allele was calculated as the average of the estimates from 3 independent methods (Chakraborty et al.
Among these, 11 that showed clear PCR products without the indication of a null allele were selected, which are listed in Table 1.
A null allele was assigned if either no amplicon was detected or agarose gel electrophoresis data showed an amplicon of a size that was beyond the usual range of fragment size of the specific VNTR locus.