Both imputation algorithms used here are restrictive in the sense that they force such missings to be imputed as one of the three habitual genotypes and do not account for the existence of null alleles or copy number variation.
As the null hypothesis, random copying does not mean that the words themselves are chosen randomly, but that they are copied randomly from others who have already used them.
Null mutations in one copy of ATP2A2, the gene encoding sarco/endoplasmic reticulum Ca2+-ATPase isoform 2 (SERcause cause Darier disease in humans, a skin condition involving keratinocytes.
Two studies of type 1 diabetes (T1D) found null associations with common copy number polymorphisms, but CNVs of low frequency and high penetrance could still play a role.
This rejects the null model that all copies are under the same functional constraints, i.e. targeted by purifying selection towards the same amino acid sequence.
Four consistent melting patterns for the α-tryptase genotype were identified with alleles carrying null, one or two copies of the α-tryptase allele.
Imaging flow cytometry also demonstrated that single-copy and null hsl1 tetraploids display an abnormal, elongated, morphology similar to that reported for null haploids in certain genetic backgrounds [ 21].
However, at the single-copy and null CLB2 gene dosages, cells exhibit a significant reduction in both viability and maximum growth rate due to a delay in the G2/M transition.
Flow cytometry demonstrated that, whilst the single-copy and null clb2 deletion mutants suffer pre-mitotic cell cycle arrest, deletions of CLB1 have no effect on cell-cycle progression.
Homozygous robo1 null embryos carrying two copies of the Robo1 rescue transgene (robo1, robo1 :: robo1) exhibited a wild-type axon scaffold, and expression of the Robo1 transgene was the same as in a wild-type background.
