RESUMO
A new mouse mutant, tail short variable (Tsv) produces a reduction deformity of the tail, growth retardation, and, in adults, a mild anemia. Genetic and embryological studies show that on all genetic backgrounds there is variable viability of Tsv/Tsv and Tsv/+ and phenotypic overlap within these and with +/+. A modifier is located to a short segment of chromosome 7, which alters the tail length of Tsv/+ mice up to 15%. The modifier, Tsv, and a coat texture mutant come from the same wild Peru mouse. The tail deformity is associated with, and may be caused by, a vascular disruption of the caudal aorta starting on day 11 of gestation. Thus Tsv appears to be different from each of the thirty known mouse mutants involving the tail. It is suggested that Tsv could be a mouse model for human conditions involving transverse terminal limb defects such as Moebius and de Lange syndromes.
Assuntos
Anemia/veterinária , Vasos Sanguíneos/anormalidades , Modelos Animais de Doenças , Genes Dominantes , Genes Letais , Transtornos do Crescimento/veterinária , Camundongos Mutantes/anatomia & histologia , Doenças dos Roedores/genética , Cauda/anormalidades , Anemia/embriologia , Anemia/genética , Animais , Animais Selvagens/genética , Mapeamento Cromossômico , Anormalidades Congênitas/classificação , Anormalidades Congênitas/genética , Anormalidades Congênitas/veterinária , Cruzamentos Genéticos , Epistasia Genética , Feminino , Ligação Genética , Variação Genética/genética , Transtornos do Crescimento/embriologia , Transtornos do Crescimento/genética , Humanos , Masculino , Camundongos , Camundongos Endogâmicos/genética , Camundongos Mutantes/embriologia , Camundongos Mutantes/genética , Muridae/genética , Peru , Fenótipo , Doenças dos Roedores/embriologia , Seleção Genética , Cauda/irrigação sanguínea , Cauda/embriologia , Cauda/patologiaRESUMO
The spontaneous appearance of a Robertsonian translocation in a laboratory colony of genetically wild Peru-Coppock mice gave the opportunity to study potential meiotic nondisjunction soon after the formation of the new chromosome and also in a hitherto untested combination of genotype and environment Metaphase II scores from the progenitor male had indicated a nondisjunction rate of approximately 10%, a figure that was confirmed by the finding of an estimated 12-16% total trisomic and probable monosomic zygotes in chromosomal studies of Day 9 embryos from heterozygous females. The chromosome studies also showed the presence of a significant excess of normal embryos that were heterozygous for the Robertsonian chromosome.
Assuntos
Aneuploidia , Grupos de População Animal/genética , Animais Selvagens/genética , Camundongos/genética , Translocação Genética , Animais , Blastocisto/fisiologia , Feminino , Heterozigoto , Cariotipagem , Metáfase , GravidezRESUMO
A population of wild mice in Peru was sampled three times over a period of 20 years. Inbreeding from each sample has shown the population to carry an unusually high frequency of visible mutants and nestling lethals. Preliminary evidence of chromosomal damage suggests an inherited tendency to some form of genetic instability.
Assuntos
Aberrações Cromossômicas , Transtornos Cromossômicos , Camundongos/genética , Mutação , Alelos , Animais , Animais Selvagens , Cruzamentos Genéticos , Geografia , PeruRESUMO
A variant of type B blood was found in three members of a family from El Salvador. In two members, both genotype BO, the blood and saliva had the characteristics of the phenotype Be1 . In the third member, genotype A2B, the red cell B antigen was stronger than in his BO genotype relatives. Thus, in this family, the presence of the A2 gene appeared to enhance the expression of the B gene.
Assuntos
Sistema ABO de Grupos Sanguíneos/genética , Adulto , El Salvador , Feminino , Variação Genética , HumanosRESUMO
A second trapping of wild mice from two sites in a Peruvian river valley confirms the unprecedented high mutant incidence established by a previous trapping. It also shows that the population may be localized. The new mutants are different from those found in the first trapping, and thus indicate a continued source of mutagenic activity either external or within the gene pool of the population. A third study is underway.