Aggressive and Mating Behaviors in Two Types of Sex Reversed Mice: XY Females and XX Males

Aggressive and mating behaviors were assessed in XX females, XY females, and XY males of the C57BL/6/J/Ei (“C57BL/6” or “B6”) strain of mouse. The Y chromosome of the XY females derives from Mus domesticus poschiavinus and the Y chromosome of the XY males derives from Mus musculus. The poschiavinus Y in the C57BL/6 background results in XY mice with either ovaries or ovotestes. Only those with ovaries were tested. These XY females appear to be endocrinologically identical to XX females. Aggressive and mating behaviors were also tested in XX males and XY males of the FVB/NtacfBR Odsex (“FVB”) strain of mouse. The XX males have a transgene inserted 1 Mb upstream of the SOX9 gene, resulting in gonadal differentiation as a testis in the absence of a Y chromosome. C57BL/6 mice were tested for aggression in an instigated resident intruder paradigm and FVB/NtacfBR Odsex mice were tested for aggression in a neutral cage paradigm. Mice of both strains were tested with opponents of the same sex chromosome complement and gonadal sex. On the C57BL/6 background, the XY males were more aggressive than the XY and XX females, but there was no significant difference between the XX and XY females in aggression. On the FVB background, the XY and XX males were equally aggressive. Mice from both C57BL/6 and FVB backgrounds were tested for mating behaviors with females in hormonal estrus. On the C57BL/6 background, the XY males mounted more than the XY females, but there was no significant difference between the XY and XX females in mounting. On the FVB background, mounting, intromissions, and ejaculations were the same in XY and XX males. The implications of these findings for the effect of sex chromosome complement on sex differences in aggression and mating in mice are discussed.     

Chromosome 9p and 10q losses predict unfavorable outcome in low-grade gliomas

The loss of chromosomes 1p–19q is the only prognostic molecular alteration identified in low-grade gliomas (LGGs) to date. Search for loss of heterozygosity (LOH) on chromosomes 1p, 9p, 10q, and 19q was performed in a series of 231 LGGs. Loss of chromosomes 1p–19q was strongly correlated with prolonged progression-free survival (PFS) and overall survival (OS) in univariate and multivariate analyses. LOH on 9p and 10q were associated with shortened PFS (P = .01 and .03, respectively) on univariate analysis. On multivariate analysis, LOH on 9p remained significant for PFS (P = .05), whereas LOH on 10q had a significant effect on OS (P = .02). Search for LOH 9p and 10q appears to be a useful complement to analysis of chromosomes 1p–19q in LGGs.     

Secondary chromosomal abnormalities of de novo acute myeloid leukemia--a first report from the Middle East

Secondary chromosome aberrations in de novo acute myeloid leukemia ( AML) are less specific and occur in addition to the primary chromosome abnormalities. Secondary chromosome aberration in acute nonlymphocytic leukemia has been recognized for many years as the most serious long-term complication of malignant disease. Our aim in this study was to focus on patients with AML associated with secondary chromosomal abnormalities in 127 consecutive Iranian leukemia patients. Methotrexate (MTX) cell synchronization and 24h non-stimulated cultures of bone marrow cells were applied to determine the incidence of chromosomal aberrations and association of specific primary and secondary chromosome anomalies according to French American British (FAB) morphological subtypes. The distribution of the secondary changes was clearly non-random. The most frequent numerical changes were -X, - Y, -7, + 8, -10 and + 22 and the most common structural aberrations were i(17q), 9q-, dicentric and marker chromosome. We believe this report is the first for de novo AML patients showing secondary chromosomal abnormalities which are quite non-random. The findings could contribute to widening knowledge of related chromosomal abnormalities.     

晚裂胚胎性染色体及18号染色体非整倍体分析

目的：分析晚裂胚胎性染色体及18号染色体数目异常情况。方法：应用荧光原位杂交技术检测晚裂胚胎X、Y及18号染色体的非整倍体情况,并与低评分的双原核（2PN）胚胎进行比较。结果：共收集85个胚胎,其中晚裂胚胎45个（不考虑形态学评分）,成功固定269个核;低形态学评分的2PN胚胎40个,成功固定243个核,用CEPX/Y、CEP18染色体探针对85个胚胎共512个核进行荧光原位杂交。晚裂胚胎组的染色体数目异常率为45.7%,其中性染色体异常率为34.5%,18号染色体异常率为38%;2PN胚胎组的染色体异常率为48.5%,其中性染色体异常率为32%,18号染色体异常率为39%。2组性染色体和18号染色体的异常率差异均无统计学意义。结论：晚裂胚胎性染色体及18号染色体数目有较高的异常发生率,与低形态学评分的2PN胚胎一样,均不适合宫腔内移植。     

Anterior positioning of sex chromosomes on the head of human sperm sorted using visible wavelengths

The human ejaculate contains subpopulations of sperm with distinct properties. Human X- and Y-bearing sperm were separated with fluorescence activated cell sorting. To avoid the use of UV light the quantitative DNA dyes DRAQ5® and Dyecycle? Vybrant® Violet were used. Sorting efficiency was similar for both dyes, but lower than what is usually obtained with the classical method involving Hoechst 33342 and UV light (60-70% enrichment, versus 80-90%). A total of 2,739 spermatozoa were evaluated, from seven distinct samples using fluorescence in situ hybridization (FISH) chromosomal probes. No differences were found in sorted and unsorted populations in terms of chromosome positioning, and numeric chromosomal anomalies were not more evident following cell sorting. Furthermore in both sorted and unsorted populations the sex chromosomes were clearly located in the anterior portion of the sperm head, while a control autosome (chromosome 18) showed no such tendency, confirming previous findings. These results suggest that other quantitative DNA dyes may be used for sex chromosome-based human sperm sorting, but with lower efficiency than the standard UV-Hoechst based assay.     

Microdissection and chromosome painting of plant B chromosomes

Plant chromosome microdissection techniques together with different isolation and amplification methods of microisolated DNA are described. Such isolated DNA was used to 'chromosome paint' B chromosomes of the dicot Brachycome dichromosomatica and the monocot Secale cereale. It is demonstrated that the specific painting of the described chromosomes was possible because of enrichment for chromosome-specific repetitive sequences, rather than the chromosome specific low- and single-copy sequences which are responsible for the painting of mammalian chromosomes. The feasibility of 'chromosome painting' of standard chromosomes in plant species with relatively small or large genomes is discussed.     

Karyotyping mouse chromosomes by multiplex-FISH (M-FISH)

Karyotyping of mouse chromosomes is a skillful art, which is laborious work even for experienced cytogeneticists. With the growing number of mouse models for human diseases, there is an increasing demand for automated mouse karyotyping systems. Here, such a karyotyping system for mouse chromosomes based on the multiplex-fluorescence in-situ hybridization (M-FISH) technology is shown. The system was tested on a number of individual mice with numerical and structural aberrations and its reproducibility and robustness verified. Mouse M-FISH should be a valuable tool for the analysis of chromosomal rearrangements in mice.     

Targeted genomic microarray analysis for identification of chromosome abnormalities in 1500 consecutive clinical cases

OBJECTIVE: To assess the yield of array-based comparative genomic hybridization. STUDY DESIGN: The results of array comparative genomic hybridization were collected on 1500 consecutive clinical cases sent to our laboratory for a variety of developmental problems. Confirmation fluorescence in situ hybridization of metaphase or interphase cells, depending on the aberration, was performed. RESULTS: Of the 1500 cases, 134 (8.9%) showed an abnormality: 36 (2.4%) showed polymorphisms or familial variants, 14 (0.9%) showed alterations of unknown clinical significance, and 84 (5.6%) showed clinically relevant genomic alterations. These included subtelomeric deletions and unbalanced rearrangements, microdeletions and reciprocal duplications, rare abnormalities, and low-level trisomy mosaicism. CONCLUSIONS: A targeted array detects a substantial proportion of abnormalities even in those patients who have already had extensive cytogenetic and/or fluorescence in situ hybridization testing. This study, although not a controlled ascertainment of subjects with specific selection criteria, accurately reflects the reality of clinical cytogenetic practice and provides an estimate of the cytogenetic abnormalities that can be identified with a targeted microarray in a diagnostic laboratory. Microarray analysis likely doubles the current yield of abnormal results detected by conventional cytogenetic analysis.     

应用Affymetrix SNP Array和FISH技术确认胎儿额外小标记染色体r（4）4p13q13.3

目的 利用AffymetriSNP Array和FISH技术鉴定额外小标记染色体的来源.方法 2013年7月1例38岁高龄孕妇来我院就诊,进行羊水染色体核型分析,G显带检测羊水和脐血胎儿染色体核型,应用AffymetrixCytoScan 750K Array基因芯片技术鉴定额外小标记染色体的片段与来源,然后运用WSH/D4Z1探针的FISH进行确认.结果 胎儿羊水G显带染色体核型为46,XX[15]/47,XX,＋mar[15],脐血G显带染色体核型为46,XX[14]/47,XX,＋mar[16];AffymetrixCytoScan 750KArray基因芯片分析结果为arr 4p13q13.3（41,593,201-72,130,692）X2-3,显示胎儿有4号染色体4p13-着丝粒-q13.3区段30.537 Mb的嵌合性重复;胎儿脐血细胞FISH检测显示28％间期细胞有4号染色体着丝粒的三体性.结论 综合应用染色体G-显带核型分析、FISH技术和AffymetrixCytoScan 750K Array芯片技术能准确确认额外微小标记染色体的来源及其片段的界定.