13 research outputs found

    Inefficient purifying selection: the mammalian Y chromosome in the rodent genus Mus

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    Two related genes with potentially similar functions, one on the Y chromosome and one on the X chromosome, were examined to determine if they evolved differently because of their chromosomal positions. Six hundred fifty-seven base pairs of coding sequence of Jarid1d ( Smcy ) on the Y chromosome and Jarid1c ( Smcx ) on the X chromosome were sequenced in 13 rodent taxa. An analysis of replacement and silent substitutions, using a counting method designed for samples with small evolutionary distances, showed a significant difference between the two genes. The different patterns of replacement and silent substitutions within Jarid1d and Jarid1c may be a result of evolutionary mechanisms that are particularly strong on the Y chromosome because of its unique properties. These findings are similar to results of previous studies of Y chromosomal genes in these and other mammalian taxa, suggesting that genes on the mammalian Y evolve in a chromosome-specific manner.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46987/1/335_2005_Article_50.pd

    Rationale for the treatment of children with CCSK in the UMBRELLA SIOP-RTSG 2016 protocol

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    The International Society of Paediatric Oncology-Renal Tumour Study Group (SIOP-RTSG) has developed a new protocol for the diagnosis, treatment, and follow-up monitoring of childhood renal tumours-the UMBRELLA SIOP-RTSG 2016 protocol (the UMBRELLA protocol). This protocol has been designed to continue international collaboration in the treatment of childhood renal tumours and will be implemented in over 50 different countries. Clear cell sarcoma of the kidney, which is a rare paediatric renal tumour that most commonly occurs in childre

    Evolutionary Strata on the Mouse X Chromosome Correspond to Strata on the Human X Chromosome

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    Lahn and Page previously observed that genes on the human X chromosome were physically arranged along the chromosome in “strata,” roughly ordered by degree ofdivergence from related genes on the Y chromosome. They hypothesized that this ordering results from a historical series of suppressions ofrecombination along the mammalian Y chromosome, thereby allowing formerly recombining X and Y chromosomal genes to diverge independently. Here predictions ofthis hypothesis are confirmed in a nonprimate mammalian order, Rodentia, through an analysis ofeight gene pairs from the X and Y chromosomes ofthe house mouse, Mus musculus. The mouse X chromosome has been rearranged relative to the human X, so strata were not found in the same physical order on the mouse X. However, based on synonymous evolutionary distances, X-linked genes in M. musculus fall into the same strata as orthologous genes in humans, as predicted. The boundary between strata 2 and 3 is statistically significant, but the boundary between strata 1 and 2 is not significant in mice. An analysis ofsmaller fragments of Smcy, Smcx, Zfy, and Zfx from seven species of Mus confirmed that the strata in Mus musculus were representative ofthe genus Mus

    Male-Driven Evolution in Closely Related Species of the Mouse Genus Mus

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    Recently, other researchers have found that closely related primate species had a lower male-to-female mutation rate ratio (α) than distantly related species. To determine if this is a general phenomenon affecting other mammalian orders, eleven species or subspecies of the rodent genus Mus and two outgroup species were compared. Intron sequences from a gene in the nonrecombining region of the Y chromosome Jarid1d ( Smcy ) and its X chromosomal gametolog, Jarid1c ( Smcx ), were analyzed in a phylogenetic context. The male-to-female mutation rate ratio for all thirteen taxa is approximately 2.5, which is similar to previous estimates in more distantly related rodents. However, when branches with lengths of more than 2.5% were removed from the analysis, the male-to-female mutation rate ratio dropped to 0.9. Thus, in closely related rodents, as in closely related primates, the male-to-female mutation rate ratio is lower than expected.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/48060/1/239_2004_Article_279.pd

    PilP, a pilus biogenesis lipoprotein in Neisseria gonorrhoeae , affects expression of PilQ as a high-molecular-mass multimer

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    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/72840/1/j.1365-2958.1997.2511618.x.pd

    High Genetic Diversity of Nontypeable Haemophilus influenzae Isolates from Two Children Attending a Day Care Centerâ–ż

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    Twenty-one nontypeable Haemophilus influenzae (NTHi) isolates from the throats of two healthy children were genotyped by multilocus sequence typing. Nine unique sequence types (STs) were identified. These STs were scattered throughout the phylogenetic tree of reported NTHi STs, demonstrating the high level of NTHi diversity found in colonized children

    Genetic Diversity of Paired Middle-Ear and Pharyngeal Nontypeable Haemophilus influenzae Isolates from Children with Acute Otitis Mediaâ–ż

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    Pulsed-field gel electrophoresis was used to determine genetic diversities of multiple nontypeable Haemophilus influenzae isolates from throat and ear specimens of eight children with otitis media. From five children, all ear and throat isolates were identical. The bacterial populations in these specimens showed less diversity than populations in throat isolates of healthy children

    Prevalence of the sodC Gene in Nontypeable Haemophilus influenzae and Haemophilus haemolyticus by Microarray-Based Hybridization â–ż

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    The sodC gene has been reported to be a useful marker for differentiating nontypeable (NT) Haemophilus influenzae from Haemophilus haemolyticus in respiratory-tract samples, but discrepancies exist as to the prevalence of sodC in NT H. influenzae. Therefore, we used a microarray-based, “library-on-a-slide” method to differentiate the species and found that 21 of 169 (12.4%) NT H. influenzae strains and all 110 (100%) H. haemolyticus strains possessed the sodC gene. Multilocus sequence analysis confirmed that the 21 NT H. influenzae strains were H. influenzae and not H. haemolyticus. An inactive sodC gene has been reported in encapsulated H. influenzae strains belonging to phylogenetic division II. Capsule-specific Southern hybridization and PCR and a lack of copper/zinc-cofactored superoxide dismutase (CuZnSOD) expression indicated that 6 of the 21 sodC-containing NT H. influenzae strains in our study were likely capsule-deficient mutants belonging to phylogenetic division II. DNA sequence comparisons of the 21 H. influenzae sodC genes with sodC from H. haemolyticus or encapsulated H. influenzae demonstrated that the sodC genes of the six H. influenzae capsule-deficient mutants were, on average, 99% identical to sodC from encapsulated H. influenzae but only 85% identical to sodC from H. haemolyticus. The sodC genes from 2/15 NT H. influenzae strains were similarly more closely related to sodC from encapsulated strains, while sodC genes from 13 NT H. influenzae strains were almost 95% identical to sodC genes from H. haemolyticus, suggesting the possibility of interspecies recombination in these strains. In summary, this study demonstrates that sodC is not completely absent (9.2%) in true NT H. influenzae strains
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