微阵列比较基因组杂交分析一例足月小样儿的染色体畸变

目的 分析一例足月小样儿的染色体畸变,探讨患儿低出生体重的原因.方法 采集临床已确诊的足月小样儿外周血并抽提基因组DNA,进行微阵列比较基因组杂交,分析患儿基因组拷贝数的改变.培养患儿及其父母外周血淋巴细胞,进行染色体核型分析并确定患儿染色体畸变的来源.结果 微阵列比较基因组杂交显示患儿在10q125.2→qter区域存在长22 Mb片段的重复,同时在15q26.2→qter区域存在长5 Mb片段的缺失.核型分析显示患儿核型为46,XY,-15,+der(15)t(10;15)(q25;q26)pat.结论 患儿在10q25.2→qter区域存在部分三体,而在15q26.2→qter区域存在部分单体,这两种染色体畸变可能均是导致患儿表现为足月小样儿的病因之一.     

五条常染色体复杂易位核型一例

孕妇女,29岁,孕1产0.平素月经规则.此次妊娠孕20周行中孕期唐氏综合征筛查为21三体高风险,故在我院行羊水细胞产前诊断.羊水细胞染色体核型分析结果:计数30个核型,分析其中5个核型,胎儿核型为46,XX,t(3;5;9;14;8)(3pter→3q27::8q21.1→8qter:5pter→5q31::3q27→3qter;9pter→9q13::5q31→5qter;14pter→14q24::9q13→9qter;8pter →8q21.1::14q24→14qter),复查脐带血结果一致,见图1.孕23周三维B超检查未见胎儿明显异常.孕妇及其丈夫外周血细胞染色体核型正常.孕妇夫妇否认致畸因子接触史.该孕妇于孕39周足月产下一女婴,未见异常表型.     

t(1;13)一家系六例

先证者（Ⅱ1）女，30岁，结婚5年孕2次，无孕期感染及有害物质接触史，均在孕9～11周不明原因流产。丈夫（Ⅱ2），32岁，夫妇非近亲结婚。查体：夫妇表型正常，身体健康，外生殖器正常。夫妇双方均做外周血淋巴细胞培养，染色体检查，G显带染色体核型分析，各计数30个中期染色体核型分裂相，先证者的核型为46，XX，1（1；13）（q43；q14）（1pter→1q43∷13q14→13qter；13pter→13q14∷1q43→1qter），其夫的染色体核型正常。     

45,XX,t(8;18)(q13;p11.2),der(13;14)(q10;q10)一例

患者女,31岁,因胚胎停育2次就诊。夫妇双方表型正常,系非近亲结婚,孕期无患病及用药史,无有毒、有害物质及放射线接触史。细胞遗传学检查:在签署知情同意书后,抽取外周血3 mL,常规制备淋巴细胞染色体,G显带分析,计数20个分裂相,分析5个,患者外周血染色体核型为:45,XX,t(8;18)(q13;p11.2)(8pter→q13∷18p11.2→pter;8qter→q13∷18p11.2→qter),der(13;14)(q10;q10)(14qter→q10∷13q10→qter)(图1);丈夫染色体核型为46,XY。     

一家系t(1;2)二例分析

病例 :　患者 ,女 ,2 9岁 ,生一男婴一天 ,因怀疑孩子为2 1三体 ,故查血染色体。细胞遗传学检查核型为 4 6 ,XX ,t(1;2 ) (1qter→ 1p2 2∷ 2q35→ 2 qter;2 pter→ 2q35∷ 1p2 2→1pter)。其子的核型为 4 7,XY ,+2 1,t(1;2 ) (1qter→ 1p2 2∷2q35→ 2 qter;2 pter→ 2 q35∷ 1p2 2→ 1pter)mat。其夫核型正常 ,家族中其他成员因故未做染色体检查。讨论 :　染色体 1号和 2号易位 ,属非同源染色体平衡易位 ,其生殖细胞可形成 18种类型的配子 ,它们分别与正常配子结合 ,则可形成 18种合子 ,其中仅一种为正常者 ,一种为表型正常的平衡易位携…     

t（4;13）平衡易位携带者世界首报一例

病例：患者,女,25岁。表型正常,婚后怀孕3次,前2次均在2个月左右自然流产,第三次在第80天左右自然流产。细胞遗传学检查：取外周血常规制备染色体,G显带,计数50个中期分裂相,核型分析10个,患者核型为46,XX,t（4;13）（4qter→4p16∷13q14→13qter;13pter→13q14∷4p16→4pter）,其丈夫核型正常。     

染色体异常核型五例

例1 女,31岁,表型及智力正常.结婚5年,怀孕2次,均于妊娠50 d左右胚胎发育停止而自发流产.清宫术刮出绒毛及完整胎囊,胎囊内未见胚胎.外周血染色体分析核型为46,XX,t(1;14) (1pter→ 1q42::14q22→ 14qter;14pter→ 14q22::1q42→1qter),见图1a;丈夫核型正常. 例2 胎儿,B超检查发现胎儿面部畸型,没有鼻子,唇裂.羊水染色体分析胎儿核型为45,XX,der(13) t(13;18)(13qter→13p13::18p10→ 18qter) mat,见图1b.母亲曾流产2次,均发生于50 d左右.母亲核型为46,XX,t(13;18) (13qter →13p13::18p10→18qter,18pter→18p10::13p13::→13pter);父亲核型正常.     

家族性(1;13)平衡易位细胞遗传学研究

作者发现一家两代染色体（1;13）平衡易位,该家系的平衡易位携带者男女均有。先证者染色体组型46,XX,t（1;13）（lqter→lpter::13q14→13qter;13pter→13q14:）。 家系病例与染色体检查 先证者:女性,31岁,结婚5年,先后在怀孕40多天流产3次,表型正常。其父母和本人非近亲婚配,母有流产史;爱人身体健康,弟妹均健康未婚。     

一例罕见的复杂染色体易位及其家系分析

患者 女,27岁.妊娠2次,均于孕2个月左右自然流产.妊娠期间无服药和不良因素接触史,患者智力和表型均正常.外周血染色体核型检查结果:45,XX,t(4;7;6)(4pter→4q31∷6p21.3→ 6pter;7pter→ 7q21∷ 4q31→ 4qter;6qter→ 6p21.3∷7 q21→ 7qter),der(13;14)(13qter→cen→ 14qter),见图1.其丈夫核型正常.     

人类同源14q 14q Robertson易位1例

作者报告1例45，XX，t(14；14)(14qter14qll：：14q12—14qter)，并讨论了14q 14q Robertson易位在人群中十分罕见的原因。指出Robertson易位的发生是非随机的，首先，着丝粒染色质区和随体柄是否容易断裂与Robertson易位有关。第14号染色体的异染色质区与第13、15号染色体不同，由于着丝粒区的重复序列有种不加选择地配对现象，逆向配对片段的U型交换导致Robertson易位．这可能是人类中两个14号染色体很难出现融合的原因。其次．随体联合把着丝粒聚集在一起，导致了Robertson易位的发生．作者统计了不同染色体间随体联合频率，发现随体联合频率高，Robertson易位频率随之增高，反之亦然，其中14和15号染色体间随体联合最低，这可能是t(14q 14q)罕见的原因。     

Partial proximal trisomy of the long arm of chromosome 5 (q13 leads to q22) resulting from maternal insertion der ins (10;5).

Five members of our study family were carriers of a balanced insertion (10;5) (q22;q13;q22). One of the children had psychomotor retardation and malformations resulting from a partial trisomy of the proximal long arm of chromosome 5, having received the maternal der(10). Amniocentesis identified another case of partial proximal trisomy in a fetus of a subsequent pregnancy. This clinical and family study is compared with two other published cases of proximal trisomy 5q.     

Simultaneous partial monosomy 10p and trisomy 5q in a case of hypoparathyroidism.

We report a case of monosomy for the distal region of the short arm of chromosome 10 (p13----ter) associated with trisomy for the terminal region of the long arm of chromosome 5 (q35.2----ter) that had originated from adjacent 1 segregation of a maternal reciprocal balanced translocation (5;10)(q35.2;p13). We review the clinical findings of previously reported cases of both partial monosomy for 10p and of partial trisomy for 5q, but to our knowledge there are no previous reports of the effects of these two chromosome anomalies together. Clinically our patient showed features typical of partial monosomy for 10p (including hypothyroidism) rather than partial trisomy 5q.     

Two cases with partial trisomy 9p: molecular cytogenetic characterization and clinical follow-up

This paper describes two patients with partial trisomy 9p and partial trisomy 14q due to 3:1 segregation from de novo maternal reciprocal translocations. The breakpoints are different from previously described 9;14 translocations and their 3:1 segregation products. The clinical phenotype of both cases is compatible with the partial trisomy 9p syndrome. We present the follow-up of both patients from birth up to age 7 years. Partial trisomy 9p is a frequently described chromosome abnormality. This does not appear to be related to a breakage sensitive locus on chromosome 9p, since the trisomic fragments of the published cases are heterogeneous. In the two cases described here, GTG-banded karyotyping suggested that the 9p breakpoints were similar; DNA marker analysis, however, showed them to be different. Such DNA studies will be necessary to define the genotype-phenotype relation in partial trisomy 9p syndrome.     

Molecular cytogenetic characterisation of partial trisomy 9q in a case with pyloric stenosis and a review

Partial trisomy 9q represents a rare and heterogeneous group of chromosomal aberrations characterised by various clinical features including pyloric stenosis. Here, we describe the case of a 1 year old female patient with different dysmorphic features including pyloric stenosis and prenatally detected partial trisomy 9q. This partial trisomy 9q has been analysed in detail to determine the size of the duplication and to characterise the chromosomal breakpoints. According to the data gained by different molecular cytogenetic techniques, such as fluorescence in situ hybridisation (FISH) with whole and partial chromosome painting probes, yeast artificial chromosome (YAC) probes, and comparative genomic hybridisation (CGH), the derivative chromosome 9 can be described as dup(9)(pter→q22.1::q31.1→q22.1::q31.1→ q22.1::q31.1→qter). Four breakpoint spanning YACs have been identified (y806f02, y906g6, y945f5, and y747b3) for the proximal breakpoint. According to this new case and previously published data, the recently postulated putative critical region for pyloric stenosis can be narrowed down to the subbands 9q22.1-q31.1 and is the result of either partial trisomy of gene(s) located in this region or a gene disrupted in 9q31.


Keywords: partial trisomy 9q; pyloric stenosis; FISH; CGH     

Two cases with partial trisomy 9p: Molecular cytogenetic characterization and clinical follow‐up

This paper describes two patients with partial trisomy 9p and partial trisomy 14q due to 3:1 segregation from de novo maternal reciprocal translocations. The breakpoints are different from previously described 9;14 translocations and their 3:1 segregation products. The clinical phenotype of both cases is compatible with the partial trisomy 9p syndrome. We present the follow‐up of both patients from birth up to age 7 years. Partial trisomy 9p is a frequently described chromosome abnormality. This does not appear to be related to a breakage sensitive locus on chromosome 9p, since the trisomic fragments of the published cases are heterogeneous. In the two cases described here, GTG‐banded karyotyping suggested that the 9p breakpoints were similar; DNA marker analysis, however, showed them to be different. Such DNA studies will be necessary to define the genotype‐phenotype relation in partial trisomy 9p syndrome. © 2002 Wiley‐Liss, Inc.     

Clinical delineation of proximal and distal partial 13q trisomy

The most relevant phenotypic features seen in both proximal and distal partial trisomy 13 have been identified from a review of 35 cases. Clinical delineation of either proximal or distal partial trisomy 13 has been demonstrated through the use of conspicuous phenotypic differences. The findings of persistent foetal Hb and increased number of nuclear projections on neutrophils are consistent findings associated with partial trisomy of a proximal segment of chromosome 13 and are diagnostic for trisomy of a partial segment of chromosome 13 that contains bands 13q12 and 13q14. The physical features of polydactyly and hemangioma have been mapped to bands 13q31 and 13q32----13qter and provide a differential diagnosis for a distal trisomic segment of chromosome 13 that may include bands 13q22----13qter. A segment of chromosome 13 has been identified that does not produce any detectable phenotypes in the triplicated state. The possible role of a triplicated 13q segment in altering expression of structural and regulatory systems elsewhere in the genome has been examined. Distinct clinical syndromes involving either a partial proximal or partial distal trisomic segment of chromosome 13 may be phenotypically defined.     

High incidence and intraclonal heterogeneity of chromosome 11 aberrations in patients with newly diagnosed multiple myeloma detected by multiprobe interphase FISH

In multiple myeloma, additional copies of chromosome 11 material, reported to confer an unfavorable prognosis, have been found in 20-45% of patients. To assess the incidence and extent of chromosome 11 aberrations, we performed interphase fluorescence in situ hybridization on CD138+ bone marrow plasma cells of 50 newly diagnosed myeloma patients, using seven locus-specific probes for chromosome 11, one for 13q14.3, and a probe set for translocation t(11;14). In 33 of 50 patients, chromosome 11 aberrations were found. Results indicated a marked intraclonal heterogeneity: in 13 patients, trisomy 11; in 10 patients, subclones with trisomy 11 and partial trisomies 11q coexisted; in 6 patients, only a partial trisomy 11q; and in 6 patients, a tetrasomy or partial tetrasomy 11. The coexistence of subclones with varying extent and copy numbers of chromosome 11 material indicates ongoing structural changes and clonal evolution. Hybridization results delineated 11q23 and 11q25 as the most frequently gained regions, which supports a relevant pathogenetic role of genes on 11q23 and 11q25. To confirm the high incidence of 11q23 gains, a further 50 patients (total n=100) were analyzed for 11q23 and 13q14.3. Myeloma with gains of 11q23 showed a low frequency of deletion 13q14.3 and may prove to be a distinct subgroup of this disease.     

Molecular and cytogenetic characterisation of an unusual case of partial trisomy/partial monosomy 13 mosaicism: 46,XX,r(13)(p11q14)/46,XX,der(13)t(13;13)(q10;q14)

A female infant with multiple malformations and mental retardation was noted to have a rare de novo chromosome abnormality involving mosaicism with two cell lines, one with a ring chromosome 13, and the other with partial trisomy 13 owing to a complex rearrangement. Cytogenetic examination excluded the presence of a t(13q;13q) cell line and showed a cell line with a marker chromosome containing two chromosome 13 long arms joined together after deletion of a part (q11→q14) of one of them. In addition, the absence of a cell line with two normal chromosomes 13 or a cell line with a t(13q;13q) implies that the ring (13) and the marker (13) arose from a single event at the first cleavage division.
The two cell lines were present in different proportions in both peripheral blood lymphocytes and skin fibroblasts. The results of microsatellite characterisation clearly indicate the paternal origin and the absence of recombination, supporting the postzygotic origin of both the ring and the marker chromosome.


Keywords: unusual mosaicism; ring 13; partial trisomy 13; partial monosomy 13     

Anatomical studies of a boy trisomic for the distal portion of 13q

A boy trisomic for the distal portion of 13q was dissected in detail and compared to 8 cases of complete trisomy 13 previously studied in our laboratory. The comparison shows that the partial trisomy 13q case did not correspond well to a muscle phenotype based on 6 variations common trisomy 13, but rather to a larger muscle phenotype that included variations less frequently observed in complete trisomy 13. Additional cases of partial trisomy 13 must be studied before these findings can be related to specific portions of chromosome 13.