RESUMEN
When compared to other model organisms whose genome is sequenced, the number of mutations identified in the mouse appears extremely reduced and this situation seriously hampers our understanding of mammalian gene function(s). Another important consequence of this shortage is that a majority of human genetic diseases still await an animal model. To improve the situation, two strategies are currently used: the first makes use of embryonic stem cells, in which one can induce knockout mutations almost at will; the second consists of a genome-wide random chemical mutagenesis, followed by screening for mutant phenotypes and subsequent identification of the genetic alteration(s). Several projects are now in progress making use of one or the other of these strategies. Here, we report an original effort where we mutagenized BALB/c males, with the mutagen ethylnitrosourea. Offspring of these males were screened for dominant mutations and a three-generation breeding protocol was set to recover recessive mutations. Eleven mutations were identified (one dominant and ten recessives). Three of these mutations are new alleles (Otop1mlh, Foxn1sepe and probably rodador) at loci where mutations have already been reported, while 4 are new and original alleles (carc, eqlb, frqz, and Sacc). This result indicates that the mouse genome, as expected, is far from being saturated with mutations. More mutations would certainly be discovered using more sophisticated phenotyping protocols. Seven of the 11 new mutant alleles induced in our experiment have been localized on the genetic map as a first step towards positional cloning.
Asunto(s)
Alquilantes/toxicidad , Etilnitrosourea/toxicidad , Genoma/efectos de los fármacos , Mutagénesis/genética , Mutación/genética , Alelos , Animales , Mapeo Cromosómico , Cruzamientos Genéticos , Femenino , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Endogámicos NZB , FenotipoRESUMEN
When compared to other model organisms whose genome is sequenced, the number of mutations identified in the mouse appears extremely reduced and this situation seriously hampers our understanding of mammalian gene function(s). Another important consequence of this shortage is that a majority of human genetic diseases still await an animal model. To improve the situation, two strategies are currently used: the first makes use of embryonic stem cells, in which one can induce knockout mutations almost at will; the second consists of a genome-wide random chemical mutagenesis, followed by screening for mutant phenotypes and subsequent identification of the genetic alteration(s). Several projects are now in progress making use of one or the other of these strategies. Here, we report an original effort where we mutagenized BALB/c males, with the mutagen ethylnitrosourea. Offspring of these males were screened for dominant mutations and a three-generation breeding protocol was set to recover recessive mutations. Eleven mutations were identified (one dominant and ten recessives). Three of these mutations are new alleles (Otop1mlh, Foxn1sepe and probably rodador) at loci where mutations have already been reported, while 4 are new and original alleles (carc, eqlb, frqz, and Sacc). This result indicates that the mouse genome, as expected, is far from being saturated with mutations. More mutations would certainly be discovered using more sophisticated phenotyping protocols. Seven of the 11 new mutant alleles induced in our experiment have been localized on the genetic map as a first step towards positional cloning.
Asunto(s)
Animales , Masculino , Femenino , Ratones , Alquilantes/toxicidad , Etilnitrosourea/toxicidad , Genoma/efectos de los fármacos , Mutagénesis/genética , Mutación/genética , Alelos , Mapeo Cromosómico , Cruzamientos Genéticos , Ratones Endogámicos BALB C , Ratones Endogámicos NZB , FenotipoRESUMEN
This article is a bibliographic review concerning mouse mutations, spontaneous, induced or genetically engineered, as models of human genetic diseases. Since the beginning of the last century, mouse models have been instrumental in the understanding of the pathogenesis of many diseases and designing of new therapies. A number of recent technological advances in embryo manipulation and many large-scale mutagenesis screens will dramatically increase the availability of new mouse models in the near future. In the "post-genomic" era, mouse mutants will have a significant role as a model system for functional genome analysis of the upcoming whole-genome information of the human and mouse genomes projects.
Asunto(s)
Animales de Laboratorio/genética , Modelos Animales de Enfermedad , Enfermedades Genéticas Congénitas/genética , Mutación , Animales , Genoma Humano , Humanos , Ratones , Ratones Transgénicos , RatasRESUMEN
This article is a bibliographic review concerning mouse mutations, spontaneous, induced or genetically engineered, as models of human genetic diseases. Since the beginning of the last century, mouse models have been instrumental in the understanding of the pathogenesis of many diseases and designing of new therapies. A number of recent technological advances in embryo manipulation and many large-scale mutagenesis screens will dramatically increase the availability of new mouse models in the near future. In the [quot ]post-genomic[quot ] era, mouse mutants will have a significant role as a model system for functional genome analysis of the upcoming whole-genome information of the human and mouse genomes projects.