一例21号环状染色体综合征的细胞遗传学和表型定位分析

目的通过对1例21号环状染色体综合征患者的细胞遗传学分析，探讨21号环状染色体的形成原因，临床表型与染色体区带的关系。方法应用染色体G带、C带、N带、高分辨显带和荧光原位杂交技术对21号环状染色体进行识别与定位。结果患儿双亲核型正常，患儿核型为46，XY，r（21）[91]／46，XY，r（21；21）（p11q22．3；p11q22．3）[5]／45，XY，-21[4]。结论21号环状染色体综合征的临床表现与21q末端缺失的多少相关，男性性别发育异常可能与21q22．3片段的缺失相关。     

46,XX,t(3;6)(q23;p24)伴习惯性流产一例

患者女，26岁，结婚4年，怀孕3胎，均于孕1～2月自然流产。妇科检查正常，夫妻双方体健，无药物及毒物接触史，表型、智力正常，非近亲结婚。细胞遗传学检查：外周血培养、制片、G显带分析，患者核型为46，XX，t（3；6）（3pte→3q23：：6p24：：→6pter；6qte→6p24：：3q23→3qter）。丈夫染色体核型正常。患者父母非近亲结婚，无不良生育史。有兄长2人均已婚，并生育正常子女。     

46,XX,t(2;4)(p15;p16)伴习惯性流产一例

患者女,29岁,结婚后怀孕6胎,均于孕80天左右流产。妇科检查正常,夫妻双方体健,无药物及毒物接触史,表型、智力正常,非近亲结婚。细胞遗传学检查:取夫妇外周血细胞培养、常规收获制片、G显带分析,患者核型为46,XX,t(2;4)(2qter→2p15∷4p16→4pter;4qter→4p16∷2p15→2pter),其     

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。     

46,XX,t(5;7)(q35;q32)inv(9)(p11q13)染色体异常一例

患者　女 ,2 7岁 ,结婚 5年。孕 4次 ,第 1胎孕 4 0多天 ,行“药流术”;第 2胎孕 5 0多天 ,行“刮宫术”;第 3、4胎孕 5 0多天 ,无明显诱因出现阴道出血 ,B超提示“宫内妊娠”,行保胎治疗无效后流产。患者表型正常 ,妇科检查未见异常。丈夫表型正常。非近亲结婚。妊娠期间无有毒、有害物质接触史、无畏寒、发热等不适病史 ,无服用药物史。患者父母表型正常 ,无不良生育史 ,生育 3女 ,表型均正常。两个妹妹无不良生育史 ,一个妹妹生一个表型正常男孩 ,另一个妹妹生两个表型正常男孩。因患者家人均在外地 ,无法追查异常染色体来源。细胞遗传…     

46,XX,t(7;20)(q11;q13)伴习惯性流产一例

患者　女 ,37岁。婚后 4年自然流产 3次 ,均在孕 40～ 5 0天阴道少量流血 ,经保胎治疗无效行刮宫术。孕期无患病、用药史及有毒物质接触史。夫妇表型、智力均正常 ,既往身体健康 ,非近亲婚配。细胞遗传学检查 :夫妇外周血淋巴细胞培养 ,常规制片 ,G显带 ,镜下计数 30个分裂相 ,分析 5个核型 ,患者核型为 46 ,XX,t(7;2 0 ) (7pter→ 7q11∷ 2 0 q13→ 2 0 qter;2 0 pter→ 2 0 q13∷7q11→ 7qer)。其丈夫核型正常。讨论　患者为平衡易位携带者 ,因无遗传物质丢失 ,故表型、智力正常 ,其生殖细胞在减数分裂中理论上形成 18种配子 ,其中 1/ 1…     

46,XX,inv(9)(q13q22)伴习惯性流产一例

患者　女 ,31岁。因习惯性流产于 2 0 0 1年 3月 12日就诊。患者怀孕 3次 ,第 1胎孕 5 0余天时 B超提示孕囊内未见胚芽 ;第 2胎孕 4月时 B超提示宫内死胎 ;第 3胎孕 6 0余天时 B超提示孕囊内未见胚芽 ,均诊断为难免流产行清宫术。患者父母非近亲婚配 ,患者为第 2胎 ,足月顺产。其母亲孕期无特殊用药史 ,无毒物和放射线接触史。患者有一姐一弟 ,发育正常 ,均已生育健康后代。二级亲属中无类似病史。查体 :患者身高 16 0 cm ,体重 5 0 kg,表型、智力正常。妇科检查外生殖器及阴毛正常 ,阴道及子宫附件检查均无明显异常。实验室检查 :血生化…     

染色体异常46,XX,t(10;13)(q26;q12)世界首报一例

病例:患者,女,36岁,外表及智力正常,结婚10余年,难受孕,曾孕产两胎,均因多发畸形死产,后进行同源IVF-ET一次,植入后因胚胎发育不良而流产.夫妇均健康,无其他妇科疾病,非近亲,父亲已去世,丈夫、母亲及妹妹染色体均正常.     

46,XX,t(5;12)(q15;q13)伴智力低下一例

病例 :患者 ,女 ,4岁半 ,第 1胎第 1产 ,足月顺产 ,因自幼智力低下 ,动作及语言发育较同龄儿明显落后 ,现生活仍不能自理 ,行为幼稚 ,入院就诊。体检 :体重 10 4kg ,身高 86 0cm ,营养状况尚差 ,生长发育迟缓 ,多动 ,智测DQ =4 8,其余检查未见异常。家族史 :父30岁 ,母 2 5岁 ,非近亲婚配 ,表型正常 ,否认家族遗传病史。其母孕期无严重疾病 ,无各种传染病史 ,未服特殊药物。双方染色体G带核型分析均正常。细胞遗传学检查 :外周血淋巴细胞培养 72h ,常规收获制片 ,G显带观察 30个中期分裂相 ,计数 30个核型。患者核型 :4 6 ,XX ,t(5 ;12…     

染色体47,XY,t(2;21)(p10;q10)+21唐氏综合征一例

病例:患儿为一男婴,6个月,因生长发育迟缓而就诊。患儿系第一胎第一产,足月顺产分娩,出生体重3500kg。母亲27岁,体健,妊娠经过顺利,未患病未接触有毒物质,父母非近亲婚配。查体:身长:56cm,体重4000g,头围:38cm,反应低下,前囟1.5cm×1.0cm,平坦,眼裂较小且明显斜向外     

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     

Congenital cardiac defect in a patient with mosaic 45,X/46,XX,i(21q) karyotype

A baby is described with 45,X/46,XX,i(21q) mosaicism. DNA analysis indicated that the abnormality arose from two independent postzygotic mutations in a 46,XX zygote, involving the paternal chromosomes 21 and X. In agreement with previous reports, most of the clinical dysmorphisms observed were consistent with Down syndrome. Moreover, congenital heart disease consisted of an atrioventricular canal associated with slight hypoplasia of the left ventricle and a mitral anulus, a complex defect including features found in both Down and Turner syndromes.     

Transmission of ring chromosome 13 from a mother to daughter with both having a 46,XX, r(13)(p13q34) karyotype

Ring chromosomes are thought to be the result of breakage in both arms of a chromosome, with fusion of the points of fracture and loss of the distal fragments. Another mechanism of ring formation is believed to be the simple fusion of chromosome ends with preservation of telomeric and subtelomeric sequences. Ring chromosome 13 was first described in 1968 and its incidence estimated at 1 in 58,000 live births. Severe phenotypes associated with large deletions of 13q have been described as "ring chromosome 13 syndrome." Features of the "ring chromosome 13 syndrome" include mental retardation (often severe), growth retardation, microcephaly, facial dysmorphism, and hand, foot or toe abnormalities. We report on a case of a mother and daughter with r(13) and mild phenotypes. Our patient, IA, had chromosome analysis performed at about 4(1/2) years of age due to some developmental delay. This revealed 46,XX, r(13)(p13q34) karyotype with no loss of any chromosomal band. Her mother, EA, was subsequently found to have the same ring 13. IA's maternal grandmother had a normal karyotype while her maternal grandfather was unavailable for testing. Fluorescence in situ hybridization (FISH) analysis showed loss of a specific subtelomeric 13q region in r(13) in the mother. Clinically, IA had macular hyperpigmentation on the chin and mild delay in speech and fine motor skills. EA, 22 years of age, had mild short stature and borderline mental retardation. To our knowledge, this is the first report of a case of familial transmission of r(13). We compare phenotypes of our cases with those from other reported cases of r(13) and discuss the possible mechanism of formation of this ring chromosome.     

Trisomy 18q: 46, XX,13q+,t(13;18)(q32;q11) in a newborn associated with multiple congenital anomalies due to paternal reciprocal translocation, 46, XY,-13,+der(13)/t(13;18)(q32;q11)

A 20-day-old female neonate presented with multiple congenital anomalies, convulsions and failure to thrive. Karyotype analysis of the proposita revealed an unbalanced translocation, 46, XX,13q+,t(13;18)(q32;qll)pat resulting in partial trisomy 18q. Her father and a 5-year-old sister were phenotypically normal, balanced translocation carriers, 46, XY, -13, + der(13),t(13;18)(q32;qll) and 46, XX,-13,+der(13),t(13;18)(q32;qll), respectively. The case presented here is the second liveborn reported with trisomy 18q and is of interest from the point of view of the structural chromosomal aberration resulting in the manifestations of most features of trisomy 18 and some of 13q monosomy. The infant died due to convulsions at the age of 2 months.     

46，XX，t（7；13）（p13；q12）一例

患者女，33岁，因习惯性流产就诊。患者表型、智力均正常，月经正常，妇科检查：子宫、附件正常。外周血染色体分析其核型为：46，Xx，t（7；13）（7qter→7p13：：13q12→13qter；13pte→＋13q12；：7p13→7pter）。其夫核型正常。父母非近亲结婚，其母无不良生育史，其妹流产2次，第3次生育一表型正常男孩。父、母、妹均未作染色体检查。     

46，XX，inv（2）（p25；q31），inv（9）（p11；q13）一例

患者　女,70天。偶尔有吐舌现象来院就诊。面容无特殊,体检正常,实验室检查各项指标正常。外周血细胞染色体检查,其核型为46,XX ,inv( 2 ) ( pter→p2 5∷q3 1→p2 5∷q3 1→qter) ,inv( 9) ( pter→p11∷q13→p11∷q13→qter)。讨论　患者为两条非同源性染色体,同时发生臂间倒位,由于染色体倒位没有遗传物质的增加或减少,所以携带者表型正常。但若倒位时有微小的丢失或重接时有基因的变异以及断裂点发生在功能效应基因上,则可能会发生某些遗传效应。由于该患者太小,其偶尔吐舌现象是否与其染色体倒位有关,有待今后继续观察。46,XX,inv(2)…     

Child with multiple congenital anomalies and mosaicism 46, XX/46,XX,del (14)(q32.3)

We report on a female infant with multiple congenital anomalies and severe developmental delay in association with a rare, terminal deletion of chromosome 14 [karyotype:mosaic. 46,XX/46,XX del (14) (q32.3) = 36%:64%]. © 1992 Wiley-Liss, Inc.     

45，X／46，Xr（X）（p22．2∷q13）一例

患儿女，10岁。第1胎，足月顺产。因生长发育迟缓，来我室就诊。患儿出生时一般情况良好，生后身高增长缓慢，就诊时身高110cm，肘外翻，外眼角上斜，有条索状性腺，表现为Turner综合征体征，但无蹼颈。双亲表型正常，非近亲婚配，患儿出生时父龄27岁，母龄25岁，其母孕期无感冒、发热、也无化学药物及放射线物质接触史，家族中无类似病史。