T H E mutant twirler, symbol Tw, of the house mouse, Mus musculus, was first recognized by the 'waltzing' behaviour which the heterozygotes show. It was later found to affect the morphology of the inner ear and, when homozygous, to cause death of new-born animals through harelip and cleft palate. This paper describes the behaviour and ear defects of heterozygotes and the appearance of homozygot...

Meckel syndrome is an inherited autosomal recessive disease. A family is described in which four persons had minor malformations related to the syndrome, suggesting the possibility of manifesting heterozygotes. It is uncertain whether these malformations represent partial expression of the disease or are coincidental. However, partial expression has been described in heterozygotes for other aut...

The frequency of chromosome aberrations in the lymphocytes of three established heterozygotes for the Bloom's syndrome gene (ages 67, 57, 46) was compared to that in controls (ages 68, 67, 61, 46, 34). The main part of the study was done on coded slides. No difference was found between the heterozygotes and the control group, except for one control (aged 46) who had a significantly higher numbe...

BACKGROUND Neurologic impairments in female heterozygotes for X-linked Adrenoleukodystrophy (X-ALD) are poorly understood. Our aims were to describe the neurological and neurophysiological manifestations of a cohort of X-ALD heterozygotes, and to correlate them with age, disease duration, mutations, X-inactivation and serum concentrations of a marker of neuronal damage, neuron-specific enolase ...

A locus influencing floral pigment intensity in the morning glory, Ipomoea purpurea, is polymorphic throughout the southeastern United States. Previous work has suggested that the white allele at this locus has a transmission advantage during mating because of the effect of flower color on pollinator behavior. The experiment described here was designed to determine whether other effects of the ...

Str(s)/str(r) heterozygotes of Escherichia coli K-12 are shown to be sensitive to the lethal as well as the inhibitory action of streptomycin. The rate of killing was lower in heterozygotes than in sensitive homozygotes, and among heterozygotes it was lower in those with a higher proportion of resistant ribosomes. These strains also differed, in a parallel manner, in the kinetics of inhibition ...

Rabbits from a variant strain called BASILEA, in which homozygotes express only lambda-type chains and heterozygotes have normal kappa/lambda ratios, were hyperimmunized with a streptococcal group A variant vaccine. Homozygotes (bas/bas) produced antibodies with lambda-chains, heterozygotes, however, produced predominantly antibodies with kappa-chains. The incidence of restricted high responder...

We measured the rate of elimination of phenylalanine by constant intravenous infusion of L-phenylalanine in 14 parents of children with phenylketonuria and in 21 subjects with a negative family history for this disease. When reciprocals of the observed elimination rates were plotted against the reciprocals of the increase in the plasma phenylalanine concentrations, approximately straight lines ...