ABSTRACT
Deletions of Y chromosome AZF locus were analyzed during a large-scale andrological and genetic examination of 810 infertile men. The search for Yq microdeletions was carried out according to the standard EAA/EMQN guidelines. The breakpoints were mapped for the deletions in AZF locus. The Y chromosome macro- and microdeletions were detected in 61 (7.5%) infertile men. The frequencies of AZF deletions during azoospermia and severe oligozoospermia amounted to 12.2 and 8.1 %, respectively. On the whole, the frequencies of Yq microdeletions and the genophenotypic correlations characteristic of various AZF deletion types comply with the relevant published data. However, spermatozoids in the ejaculate sediment of men with completely deleted AZFa region or AZFb+c deletions (from solitary spermatozoids to several dozens) were detected for the first time. It was demonstrated that the breakpoints were localized between AZFa and AZFb regions proximally to AZFb+c microdeletions for the majority of cytogenetically detectable deletions in the Y chromosome long arm. This indicates that the mechanisms underlying Yq macro- and microdeletions are somewhat different. The issues related to the role of Y chromosome deletions in the origins of monosomy for X chromosome and X/XY mosaicism are discussed.
Subject(s)
Chromosome Deletion , Chromosomes, Human, Y/genetics , Oligospermia/genetics , Humans , Infertility, Male/genetics , Male , Physical Chromosome MappingABSTRACT
A linear fragment of the pRK3lacZ plasmid (RSVlacZ) and circular DNA of pCMVlacZ were injected into rabbit zygotes. The embryos were cultured for 24-72 h and analyzed with chromogenic X-gal substrate for bacterial beta-galactosidase. The expression of RSVlacZ DNA was revealed in 6-16-cell embryos. The expression of pCMVlacZ plasmid was low in 2-blastomere embryos, and high in 4-16-cell embryos. In both cases, no beta-galactosidase activity was observed in one-cell embryos. The results obtained indirectly suggest selective and stepwise gene activation in the course of rabbit embryo development.
Subject(s)
Blastocyst , DNA, Circular/genetics , Gene Expression , Transfection , Animals , Avian Sarcoma Viruses/genetics , Chromosome Mapping , Cytomegalovirus/genetics , Microinjections , Plasmids , Promoter Regions, Genetic , Rabbits , Repetitive Sequences, Nucleic AcidABSTRACT
Variable polymorphic patterns were detected using EcoRI-SalI fragment of bovine rDNA, including 3'-end of 28S rRNA gene with the adjacent portion of the transcribed spacer, as a probe for hybridization. Some features of these polymorphic patterns are similar to DNA fingerprints detected with the M13 probe. Bovine rDNA spacer polymorphism was used as a molecular genetic marker for population analysis of individual specific patterns of 4 cattle breeds with the help of the Jeffreys' method. It was supposed that the probability of identical fingerprints appearance could be the characteristics of heterogeneity of cattle populations. The observed length of polymorphic gragments ranged from 2000 to 6000 bp. The mean number of fragments per individual for all breeds was 15.05. The probability of identical patterns appearance was very high: from 1.18 x 10(-5) in ajshir's breed to 1.43 x 10(-7) in "white and black"s' breed. So, high probability seems to be dependent on the high allelic frequency and the way of breeding.
Subject(s)
DNA, Ribosomal/genetics , Polymorphism, Genetic/genetics , Polymorphism, Restriction Fragment Length , Transcription, Genetic/genetics , Animals , Cattle , DNA/isolation & purification , DNA Fingerprinting , Female , Genetic Markers/genetics , Molecular Weight , Nucleic Acid HybridizationABSTRACT
The restriction map of bovine 28S rRNA gene and adjacent 5'-spacer region was determined. The high level of intragenomic and population length polymorphism of EcoRI-BamHI restriction fragment was demonstrated to originated from the 3'-end of 28S rDNA and 5'-spacer of rDNA repeat. This polymorphism is more pronounced than the ones revealed in human and murine rDNA repeats and could be compared with genomic fingerprints obtained by M13 or minisatellite DNA hybridization probes. From family blot-panel analysis we concluded that in progeny only parental sets of length variants were inherited and that the copy number of definite variants does not change in the progeny as well. From these results it was proposed that the definite sets of linked in genome length variants are inherited independently from each other.
