The lethal effect of homozygosity of the gene for waltzer-type, a neurological mutant in Mus musculus☆

[摘要] ThehomozygousconditionofthegeneWtforwaltzer-typeislethal,usuallyby11daysofgestation.ThisconclusionissupportedbygeneticdatafromWt+×Wt+andfromWt+×+/+matings.Abnormalappearanceofthebrain,failureoflensdevelopmentandlessproliferativeactivityintheoticvesiclescharacterizedallhomozygotesat1012–11daysofgestation.Themajoritywereretardedingrowthanddevelopment.Anabnormaldegreeofpycnosiswasnotedinvariousstructures,suchasthespinalganglia,butthepicturewasnotconsistentforalltheabnormalembryos.Faultydevelopmentofthehindbrainwasobservedmorphologicallyinsome9–10-dayembryos,buttheproportionofaffectedembryosatthisagewasconsiderablylessthantheexpected25%WtWt.Histologicallyafewembryosat9daysandmoreat10dayshadabnormalbrainssimilartothosein1012–11-dayhomozygotes.Theincreasewithageinthepercentageofdefinitelyabnormalbrainssuggestsvariationinthetimeofexpressionofthegenotype.

[学科分类] 生物科学（综合）