用高分辨G带和人工细菌染色体荧光原位杂交技术分析中国儿童孤独症患者的染色体改变

目的 检测中国儿童孤独症患者的特征性染色体改变。方法 应用高分辨G带和人工细菌染色体(bacterial artificial chromosome，BAC)荧光原位杂交(flourescence in situ hybridization，FISH)分析68例中国儿童孤独症患者的染色体改变。结果 用G带分析观察到有染色体改变的4例患者，分别为1例t(4；6)(q23-24；p21)、1例21p 和2例9号染色体臂间倒位。BAC FISH进一步证实易位病例，而且更精确[t(4；6)(q25-26；p21-1)]；涉及7号、15号、2号染色体的BAC FISH均未观察到文献中报道的染色体改变；而9号染色体的臂间倒位和21p 因无BAC克隆而无法证实。结论 用G带和BAC FISH发现少数中国孤独症患者有染色体改变，但远没有文献中报道的10％～48％那么高。BAC FISH有助于精确地确定染色体易位断裂点。     

Detection of numerical alterations of chromosome 1 in cytopathological specimens of breast tumors by chromogen in situ hybridization

To investigate the effectiveness of chromogen in situ hybridization (CISH) in the diagnosis of breast tumors, numerical alterations of chromosome 1 were examined by CISH and fluorescence in situ hybridization (FISH) methods, and the presence of der(16)t(1;16) was also examined by FISH in imprinted cytology specimens from resected tissues of 14 carcinomas and five non-malignant lesions. The modal signal counts of chromosome 1 were compared between the specimens processed by CISH and FISH for each case. Aneusomies of the long arm of chromosome 1 were detected in 10 (71%) carcinomas as the major clones by both methods. In addition, one atypical papilloma demonstrated tetrasomy of 1q12 as a major clone by CISH, but such a clone was at first overlooked by FISH. Four other benign lesions showed disomic 1q12 signals as a major clone by both CISH and FISH. As additional information from FISH, eight cancers showed structural or numerical alterations of chromosome 16, and four showed der(16)t(1;16). In total, 10 carcinomas showed chromosome 16 alterations, and all of these overlapped with the carcinomas with 1q12 aneusomies. The CISH method provided almost the same results as the FISH method, and both methods were considered applicable in supportive diagnosis of cytological specimens of breast tumors. In addition, the CISH method was superior in the detection of numerical alterations in carcinoma cells by referring to the morphology of cells and in the detection of significant clones which might be missed under dark-field microscopy.     

De novo 13q partial duplication identified by cytogenetic, biochemical and molecular approaches

A 3.5-month-old female infant manifesting dysmorphic facies, developmental delay and failure to thrive was referred for cytogenetic evaluation. Peripheral lymphocytes revealed three chromosomally distinct cell lines: 46,XX/46,XX,10p+/47,XX,10p+,+mar. Dermal fibroblasts revealed only the 46,XX,10p+cell line. High resolution G-, R-, and Q-banding suggested that the extra chromosomal material (10p+) represented a duplication of the segment 13q14----13qter. Parental karyotypes were normal. As absolute identification of de novo chromosomal abnormalities, based solely on cytogenetic studies, is sometimes difficult, both biochemical and molecular approaches were undertaken to elucidate this abnormality in more detail. Dosage effects were examined using esterase D (localized to 13q14.1) and the DNA probes p1E8 and p9A7 (localized to 13q22 and 13q31/32, respectively). These studies suggested the presence of only 2 copies of esterase D, but 3 copies of both DNA probes, allowing identification of the breakpoint at 13q14.2.     

Novel isodicentric chromosome 18 in an abnormal infant with a mosaic karyotype [46, XY/46,XY, –18,+ dic(18)(q12.2)]

A previously unreported isodicentric chromosome 18 was discovered in an abnormal infant boy whose mosaic karyotype was 46, XY/46,XY,–18, + idic(18)(q12.2). His constellation of congenital anomalies was typical of the 18q-syndrome. The clinical and cytogentic characteristics of this patient are reported, and the literature concerning isochromosomes of 18 is reviewed.     

荧光原位杂交同时检测精子X和Y染色体的方法

用实验手段分离X和Y染色体精子或富集特定性别染色体精子．对于预防性连锁遗传病具有潜在应用价值。建立精子X和Y染色体鉴定方法对于评估分离或富集特定性别染色体效果至关重要。本文介绍采用CY3TM和FlourXTM探针作荧光原位杂交（FISH），同时检测精子Y和X染色体。10份正常精液标本分析结果显示：X染色体精子为50．23％，Y染色体精子为49．77％；有效杂交率达91．99％。FISH方法比传统的精子染色体核型分析和奎纳克林染色检查Y荧光小体更具有简易、特异和快速的优点。     

Three dinucleotide repeat polymorphisms at the D8S1217, D8S1220, and D8S1221 loci

Three polymorphic dinucleotide (CA) repeat clones were isolated from a CEPH mega-YAC clone (936F7), and were localized to chromosome 8 using a panel of 13 mouse/human somatic cell hybrids.     

Rapid molecular cytogenetic analysis of X-chromosomal microdeletions: Fluorescence in situ hybridization (FISH) for complex glycerol kinase deficiency

Diagnosis of X-chromosomal microdeletions has relied upon the traditional methods of Southern blotting and DNA amplification, with carrier identification requiring timeconsuming and unreliable dosage calculations. In this report, we describe rapid molecular cytogenetic identification of deleted DNA in affected males with the Xp21 contiguous gene syndrome (complex glycerol kinase deficiency, CGKD) and female carriers for this disorder. CGKD deletions involve the genes for glycerol kinase, Duchenne muscular dystrophy, and/or adrenal hypoplasia congenita. We report an improved method for diagnosis of deletions in individuals with CGKD and for identification of female carriers within their families, using fluorescence in situ hybridization (FISH) with a cosmid marker (cosmid 35) within the glycerol kinase gene. When used in combination with an Xq control probe, affected males demonstrate a single signal from the control probe, while female carriers demonstrate a normal chromosome with two signals, as well as a deleted chromosome with a single signal from the control probe. FISH analysis for CGKD provides the advantages of speed and accuracy for evaluation of submicroscopic X-chromosomal deletions, particularly in identification of female carriers. In addition to improving carrier evaluation, FISH will make prenatal diagnosis of CGKD more readily available. © 1995 Wiley-Liss, Inc.     

Characterization of an inversion duplication of the short arm of chromosome 8 by fluorescent in situ hybridization

A de novo chromosome aberration in a woman with severe mental retardation and minor anomalies has been characterized cytogenetically. The patient's karyotype was described as 46, XX, inv dup (8)(p12 → p23.1). Previous Southern blot dosage studies with the marker locus D8S7 demonstrated that the patient was monosomic for this locus, suggesting that the rearrangement generated a duplication-deficiency chromosome. We have reinvestigated this patient using fluorescent in situ hybridization with chromosome 8 cosmids and an Alu-PCR product specific for 8p. These studies have confirmed directly that the duplicated chromosome also has undergone deletion. © 1992 Wiley-Liss, Inc.     

A murine TSPY

Sequences homologous to human and bovine TSPY were isolated from M. musculus testicular cDNA, and a nearly full-length gene was polymerase chain reaction (PCR) amplified from mouse genomic DNA. This gene is apparently non-functional. Contrary to the situation encountered in species along the primate and artiodactyl lineages, in which TSPY is moderately repetitive, murine Tspy appears to be single copy. Murine Tspy is located on Yp, i.e. in the same syntenic group as in man. Sequence comparisons of murine, human and bovine TSPY exons suggest that TSPY became non-functional during rodent evolution.