Describes an experimental cross in mice that can be used to define and map induced germ-line mutations that map to a single chromosome. The cross is a modification and extension of a conventional three-generation recessive mutagenesis screen. Includes: The Mutagenesis Breeding Plan; Consomic Strains; Generating Mutations; Generating and Genotyping G2 Females; Genotyping G3 Progeny; Phenotyping G4 Progeny; etc.. - [Read A Targeted Screen to Detect Recessive Mutations that have Quantitative Effects Protocol]
Investigators can utilize X chromosome inactivation (methylation) to determine the clonality status of a tumor or premalignant lesion in females. The technique is based on a methylation-sensitive restriction enzyme and analysis of a polymorphic locus on the X chromosome. Clonal cell populations will show "loss" of the non-methylated allele after restriction digest. The assay can be performed on DNA recovered from microdissected samples. Both frozen tissue and fixed-embedded tissue can be used. - [Read Clonality - X Chromosome Inactivation Assay Protocol]
Protocol describes a method for vasectomy in which the vas deferens is accessed through the abdominal wall. Mice are ready for mating after ~10-14 days. Vasectomized males can be bred with fertile females to obtain plugs for timed matings. The pseudopregnant females can then be used for oviduct and uterine transfers. For an alternative protocol, see Vasectomy for Generation of Sterile Males: Access via Scrotal Sac. - [Read Vasectomy for Generation of Sterile Males: Access via Abdominal Wall Protocol]
Protocol describes a method for vasectomy in which the vas deferens is accessed through the scrotal sac. Mice are ready for mating after ~10-14 days. Vasectomized males can be bred with fertile females to obtain plugs for timed matings. The pseudopregnant females can then be used for oviduct and uterine transfers. - [Read Vasectomy for Generation of Sterile Mouse Males: Access via Scrotal Sac Protocols]
Protocol describes the general procedure for creating mutations in the DNA of Drosophila by exposure to X-rays. Irradiation of cells with X-rays creates double strand breaks (DSBs) in DNA. Mutations introduced in the DNA of germ line cells (sperm) are propagated by mating the exposed males to virgin females. The progeny of this cross can be mated to each other so that a percentage of the subsequent offspring will have two copies of the same mutant allele. - [Read X-Ray Mutagenesis of Drosophila Protocol]