PubMed Health⌕ Search

Biomedical subjects

Z Taib

Publications and source records attributed to Z Taib.

5 recordsLinked to original sources

Evolutionary aspects of the genomic organization of rat chromosome 10.

Using FISH and RH mapping a chromosomal map of rat chromosome 10 (RNO10) was constructed. Our mapping data were complemented by other published data and the final map was compared to maps of mouse and human chromosomes. RNO10 contained segments homologous to mouse chromosomes (MMU) 11, 16 and 17, with evolutionary breakpoints between the three segments situated in the proximal part of RNO10. Near one of these breakpoints (between MMU17 and 11) we found evidence for an inversion ancestral to the mouse that was not ancestral to the condition in the rat. Within each of the chromosome segments identified, the gene order appeared to be largely conserved. This conservation was particularly clear in the long MMU11-homologous segment. RNO10 also contained segments homologous to three human chromosomes (HSA5, 16, 17). However, within each segment of conserved synteny were signs of more extensive rearrangements. At least 13 different evolutionary breakpoints were indicated in the rat-human comparison. In contrast to what was found between rat and mouse, the rat-human evolutionary breaks were distributed along the entire length of RNO10.

Animals↗

Genetic identification of multiple susceptibility genes involved in the development of endometrial carcinoma in a rat model.

There are clear indications that inheritance plays an essential role in certain cases of human endometrial cancer, and there are at least 2 forms of early-onset heritable endometrial adenocarcinomas (EACs). Females of the BDII inbred rat strain are known to be genetically predisposed to endometrial carcinoma, and we have performed a genetic analysis of susceptibility to endometrial cancer in this strain. F(2) populations were generated by crossing BDII females with males from 2 different strains with a low incidence of EAC, and the occurrence of endometrial cancer was studied. Three chromosome regions associated to EAC susceptibility were identified, and the susceptibility genes in these regions were designated Ecs1, Ecs2 and Ecs3. Our results indicate that the genes affecting susceptibility to EAC are different in the 2 crosses, suggesting that the genes behind the susceptibility in BDII animals may interact with different genes in different genetic backgrounds.

Adenocarcinoma↗

The western Swedish BRCA1 founder mutation 3171ins5; a 3.7 cM conserved haplotype of today is a reminiscence of a 1500-year-old mutation.

The most recurrent BRCA1/BRCA2 mutation in Sweden is the BRCA1 mutation 3171ins5. In the western part of Sweden this mutation accounts for as much as 77% of identified mutations in these two genes. Our aim was to analyse in detail the haplotype and founder effects of the 3171ins5 and furthermore attempt to estimate the time of origin of the mutation. In the study we included eighteen apparently unrelated families with hereditary breast and/or ovarian cancer. At least one individual in each family had previously tested positive for the 3171ins5 mutation. Polymorphic microsatellite markers were used for the haplotype analyses. The markers were located within or flanking the BRCA1 gene spanning a region of 17.3 cM. We found several different haplotypes both for disease alleles and for the normal alleles. However, a conserved haplotype of 3.7 cM was observed in the 3171ins5 carriers spanning over four markers located within or very close to the BRCA1 gene. As this haplotype was not present in any of the normal controls it is highly likely that this is a mutation identical by descent, i.e. a true founder. The results from the haplotype analyses were used to estimate the age of the mutation. Estimations based on the P(excess) and linkage disequilibrium gives a first appearance of the mutation sometime around the 6th century, approximately 50 generations ago.

BRCA1 Protein↗

A note on modelling the dynamics of budding yeast populations using branching processes.

A multitype branching process is proposed as a model for the behaviour of populations of the budding yeast Saccharomyces Cerevisiae. Using the idea of branching processes counted by random characteristics, we are able to obtain explicit expressions describing different aspects of the asymptotic composition of such populations. The main purpose of this note is to show that the branching process approach is an alternative to deterministic population models based on differential equation methods.

Mathematics↗