Turner综合征患者标记染色体的鉴定与分析

目的 分析11例携带标记染色体的Turner综合征患者的核型,研究这类染色体的表型效应。方法 选择11例具Turner综合征表型的患者,常规核型分析均显示为携带标记染色体的嵌合体,其中6例标记染色体呈环状。患者G带核型表示为mos．45,X／46,X,＋mar或者mos．45,X／46,X,＋r．以X／Y着丝粒探针,应用荧光原位杂交（FISH）技术分析这些标记染色体起源,对其中2例较大的环状染色体,结合反向染色体涂染确定断裂位点,比较不同断裂位点的标记染色体的遗传学效应。结果11例患者所携带的标记染色体均为环状染色体,r（X）的断裂位点分别位于Xp22、Xq22、Xq24、Xq26等。结论 Turner综合征患者的标记染色体主要来源于X染色体,且表现为r（X）形式。r（X）均以嵌合型的形式存在。     

Prenatal detection and characterization of a small supernumerary marker chromosome (sSMC) derived from chromosome 22 with apparently normal phenotype

OBJECTIVE: To present prenatal findings and molecular cytogenetic characterization of a small supernumerary marker chromosome (sSMC) derived from chromosome 22 with apparently normal phenotype. CASE AND METHODS: An amniocentesis was performed at 15 weeks' gestation and a small marker chromosome in the female fetus of a twin pregnancy was noted. A second amniocentesis was performed at 18 weeks; G-banding analysis on amniotic cells confirmed the small marker chromosome found in the female fetus. Both parents and the male twin fetus had normal karyotypes. Spectral karyotyping (SKY), Fluorescence in situ hybridization (FISH) analyses with chromosomal specific whole chromosome painting probe (WCP 22) and alphoid satellite DNA probe (D22Z4) were used to identify the origin of the sSMC. The make-up of the sSMC was characterized by further FISH studies with chromosome region specific probes. The twin babies were delivered normally at 35 weeks' gestation. The female neonate with sSMC did not show any dysmorphic features, except for a type II atrial septum defect (ASD) at birth. She was found to be developing and growing normally at her 2-year follow-up. RESULTS: Conventional G-banding study confirmed the presence of a sSMC with bi-satellites. SKY and FISH with D22Z4 probes showed that the marker originated from chromosome 22. FISH studies using 4 locus-specific DNA probes in the 22q11.2 region (N25 probe to detect the D22S75 locus within the velocardiofacial syndrome/DiGeorge syndrome (VCFS/DGS) critical region, a clone to detect the Bid locus just distal to the cat eye syndrome (CES) critical region and two clones 77H2 and 109L3 to detect the proximal end of the CES critical region, (CECR2 and CECR7), did not reveal any hybridization signal with the marker chromosome. The karyotype of the fetus was 47,XX,+ mar. ish der(22) (SKY+,D22Z42 + ,CECR7-,CECR2-, BID-,D22S75-). CONCLUSION: The supernumerary marker chromosome in this case was a de novo inv dup(22)(q11.2) and contained a duplicated proximal long arm region < 400 kb from the centromere; it did not appear to affect the phenotype of the child.     

A comparative genomic hybridization study in a 46,XX male

OBJECTIVE: To identify Y chromosome material in an azoospermic male with an XX karyotype.DESIGN: Case report. SETTING: Faculty of medicine and Centro de Patologia Celular (CPC) medical center. PATIENT(S): A 33-year-old man with infertility. INTERVENTION(S): G-banding, fluorescence in situ hybridization (FISH), polymerase chain reaction (PCR), and comparative genomic hybridization (CGH). MAIN OUTCOME MEASURE(S): FISH for X and Y chromosomes, PCR for the SRYgene and amelogenin gene in the Xp (AMGX) and (AMGY), and losses or gains with CGH. RESULT(S): FISH analysis using X and Y chromosome-specific probes showed an X chromosome containing Y chromosome sequences on the top of the short arm; this Y chromosome region was not visible by conventional cytogenetic analysis. PCR amplification of DNA showed the presence of the sex-determining region of the Y chromosome (SRY) and the amelogenin gene in the pseudoautosomal boundary of the X chromosome (AMGX). CGH confirmed the presence of the chromosome region Yp11.2-pter and detected the presence of the two otherwise normal X chromosomes. CONCLUSION(S): The two Xpter (XPAR1) pseudoautosomal regions present in this XX male suggest the need to reevaluate XX males using CGH and PCR to characterize the clinical variability in XX males due to genes other than those located on the Y chromosome.     

Prenatal diagnosis and molecular cytogenetic characterization of a small supernumerary marker chromosome (sSMC) inherited from her mosaic sSMC(15) mother and a literature review

ObjectiveWe characterized a maternally inherited small supernumerary marker chromosome (sSMC) derived from chromosome 15 according to prenatal detection and made a review on the prenatal sSMC(15) cases with mosaic maternal inheritance.Case reportA 29-year-old woman underwent amniocentesis at 19 weeks of gestation due to the high risk of Down syndrome in maternal serum screening. No abnormalities were observed in prenatal ultrasound findings. G-banding analysis revealed a karyotype of 47,XX,+mar. Subsequently, we recalled the couple back for chromosomal analysis. The father's karyotype was normal while the mother's karyotype was 47,XX,+mar[15]/46,XX[35]. Molecular genetic analysis was utilized to identify the marker chromosome. The chromosomal microarray analysis (CMA) results of the mother showed there existed microduplications in the locus of 14q32.33, 15q21.1, 19p12 and Xq26.2, respectively. Then Fluorescence in situ hybridization (FISH) using specific probes for chromosomes 13/21, 14/22, and 15 was applied on the mother and the fetus. And the marker chromosomes for the mother and the fetus were all finally identified as inv dup(15) (D15Z1++, SNRPN-, PML-), which illustrated that the fetus inherited the sSMC(15) from her mother. Finally, a healthy female infant was delivered with no phenotypic abnormalities at 39 weeks.ConclusionThe combined utilization of the molecular genetic technologies, such as FISH and CMA, plays a critical role in the identification of the origins and genetic constitutions of sSMC, which would make a significant contribution to genetic counseling and prenatal diagnosis.     

Prenatal and postnatal characterization of Y chromosome structural anomalies by molecular cytogenetic analysis

We describe three cases in which we used fluorescence in situ hybridization (FISH), polymerase chain reaction (PCR) and comparative genomic hybridization (CGH) to characterize Y chromosome structural anomalies, unidentifiable by conventional G-banding. Case 1 was a 46,X,+mar karyotype; FISH analysis revealed an entire marker chromosome highlighted after hybridization with the Y chromosome painting probe. The PCR study showed the presence of Y chromosome markers AMG and SY620 and the absence of SY143, SY254 and SY147. CGH results confirmed the loss of Yq11.2-qter. These results indicated the presence of a deletion: del(Y)(q11.2). Case 2 was a 45,X [14]/46,XY[86] karyotype with a very small Y chromosome. The PCR study showed the presence of Y chromosome markers SY620 and AMG, and the absence of SY143, SY254 and SY147. CGH results showed gain of Yq11.2-pter and loss of Yq11.2-q12. These results show the presence of a Yp isodicentric: idic(Y)(q11.2). Case 3 was a 45,X,inv(9)(p11q12)[30]/46,X,idic(Y)(p11.3?),inv(9)(p11q12)[70] karyotype. The FISH signal covered all the abnormal Y chromosome using a Y chromosome paint. The PCR study showed the presence of Y chromosome markers AMG, SY620, SY143, SY254 and SY147. CGH only showed gain of Yq11.2-qter. These results support the presence of an unbalanced (Y;Y) translocation. Our results show that the combined use of molecular and classical cytogenetic methods in clinical diagnosis may allow a better delineation of the chromosome regions implicated in specific clinical disorders.     

Prenatal diagnosis of jumping translocation involving chromosome 22 with ultrasonographic findings

We report on the prenatal diagnosis and ultrasonographic findings of a second-trimester fetus with jumping translocation involving chromosome 22. A 28-year-old gravida 2, partus 1, Turkish woman was referred for genetic counselling and ultrasonographic examination at 18 weeks' gestation because of a high risk of trisomy 21 in triple test. Prenatal ultrasonography showed tetralogy of Fallot with a diverticular dilatation of the pulmonary artery, flattened brow, complete absence of the right upper limb, hypospadias, oligodactyly (three digits) in left hand and in both feet, and hyperechogenic abdominal foci. Amniocentesis revealed a karyotype of 46,XY[4]/46,XY,-8,+ der(8),t(8;22)(q24.3;q11.21)[2]/45, XY,-22,-8,+ der(8)t(8;22)(q24.3;q11.21)[22]/45,XY,-22,-5,+ der(5)t(5;22)(q35.3;q11.21)[44]. A C-banding and FISH study with a specific centromeric probe (D14Z1/D22Z1) for chromosome 22 was made. In our case, partial monosomy for the regions 22q11.21-->22pter, 8q24.3-->8qter and 5q35.3-->5qter may partially explain the fetal malformations.     

A familial Xp+ chromosome detected during fetal karyotyping,which is associated with short stature in four generations of a Turkish family

The short-stature homeobox-containing gene (SHOX) on chromosome Xp22.3 was recently identified as an important determinant of the stature phenotype. Deletions of the SHOX gene, some of them due to structural chromosome abnormalities, have been described in patients with idiopathic short stature and Leri-Weill syndrome. Additionally, haploinsufficiency of SHOX is a main cause for short stature seen in patients with Turner syndrome.Here we report an unusual X-chromosome abnormality, which was detected during a fetal karyotyping performed because of a previous child with Down syndrome. GTG banding demonstrated an extra chromosome segment on the terminal part of the short arm of chromosome X in the index case (karyotype: 46,X,Xp+). The same chromosomal abnormality was found in the mother and the maternal grandmother. All carriers of this chromosomal abnormality presented with short stature but no other associated symptoms.Whole chromosome painting of X revealed a homogeneous painting of the abnormal X chromosome indicating that no other chromosome was involved. Additional FISH studies with probe DXS1140 (Kallmann probe at Xp22.3), Quint-Essential X-Specific DNA (DMD probe at Xp21.2), XIST (at Xq13.2), and Tel Xq/Yq were performed, and no abnormality was observed in the intensities or the localizations of the probes signals. However, applying a specific SHOX gene probe (derived from cosmid LLNONO3M34F5) showed a loss of signal on the derivative X chromosome. Our results show that the Xp+ generation led to a deletion of the complete SHOX gene and caused short stature in the presented family.     

A case of an infertile male with a small supernumerary marker chromosome negative for M-FISH and containing only heterochromatin

Aim  To describe the case of a 32-year-old infertile male with small supernumerary marker chromosome (sSMCs) in 80% of peripheral lymphocytes. Methods  G-banding, C-banding, STRP analysis, M-FISH and molecule diagnosis of Y-chromosomal microdeletions were performed to determine the origin of sSMCs. Results  The karyotype of this patient was established as 47, XY, +mar/46, XY. C-banding showed that the marker chromosome was composed of heterochromatin without visible euchromatic material. No positive result was obtained in STRP, M-FISH and the microdeletion analysis of Y- chromosome. Conclusions  The small supernumerary marker chromosome could play a causative role in male infertility although the mechanism remains to be elucidated. Capsule   We report a case of an infertile male with heterochromatic sSMCs, and analyze the relationship between infertility and heterochromatic sSMCs.     

原发闭经表型的细胞遗传学病因研究

目的:探讨原发闭经表型的细胞遗传学病因。方法:运用常规的染色体核型分析技术及FISH、C-带和Q-带技术,分析25例原发闭经表型患者的染色体核型。结果:25例原发闭经表型病例中,18例核型异常,占72.0%。异常核型病例分别为:45,X 8例、46,XY 2例,等臂X 1例、嵌合核型4例(分别为45,X细胞系与不同的结构异常性染色体细胞系的嵌合体)、X长臂末端缺失1例、X-常染色体平衡易位2例。除这18例异常核型患者外,尚有7例为先天性无子宫、无阴道的原发闭经患者未检出核型异常。结论:X染色体数目单体、X结构异常、X染色体数目单体细胞系与结构异常性染色体细胞系的嵌合体核型、XY性发育异常(DSD)、X-常染色体平衡易位都可导致原发闭经表型。常规G-显带技术与C-带、Q-带技术及FISH技术相互结合,有助于进一步准确诊断核型。     

应用荧光原位杂交技术快速诊断胎儿染色体数目异常

目的 探讨荧光原位杂交（ｆｌｕｏｒｅｃｅｎｔ ｉｎ ｓｉｔｕ ｈｙｂｒｉｄｉｚａｔｉｏｎ,ＦＩＳＨ）技术在快速产前诊断胎儿染色体数目异常中的价值。方法 对２０例孕１６￣３６周,有产前诊断指征者,在Ｂ超引导下经腹抽取羊水后,应用Ｘ、Ｙ、１８号染色体着丝粒探针１３ｑ１４－ｑ２１和２１ｑ１１特异性探讨,对未培养的羊水间期细胞进行ＦＩＳＨ,然后用荧光显微镜进行观察,并用Ａｐｐｌｉｅｄ ｉｍａｇｉｎｇ染色体     

Demonstration of a mechanism of aneuploidy in human oocytes using Multifluor fluorescence in situ hybridization

OBJECTIVE: To evaluate the potential of Multifluor fluorescence in situ hybridization (M-FISH) for karyotyping the human oocyte and first polar body. DESIGN: Prospective case study. SETTING: Research laboratories, university hospital. PATIENT(S): A 33-year-old woman with polycystic ovary syndrome who was undergoing ovarian stimulation and ICSI. MAIN OUTCOME MEASURE(S): Karyotyping of all chromosomes within an oocyte and first polar body, using GV stage oocytes matured to metaphase II in vitro. RESULT(S): Oocyte hyperploidy was diagnosed by M-FISH to be 23, X +15 cht +19 cht +22 cht. The correspond- ing polar body was hypoploid, with a karyotype of 23, X -15 cht -19 cht -22 cht. This was due to unbalanced predivision at meiosis I. Reprobing confirmed karyotype assignments for chromosomes X, 13, 18, and 21. CONCLUSION(S): The mechanism involved in maternally derived aneuploidy can be defined by using M-FISH to simultaneously karyotype both oocyte and first polar body chromosomes at metaphase II. Multifluor FISH may be useful for investigative studies of maternally derived aneuploidy, which is a major cause of preimplantation waste in natural and assisted reproduction.     

Prenatal diagnosis of a familial complex chromosomal rearrangement involving chromosomes 5, 10, 16 and 18

We report one case of a familial complex chromosomal rearrangement (CCR) involving four different chromosomes 5, 10, 16 and 18. The CCR was detected prenatally at 20 weeks' gestation because of advanced maternal age and history of recurrent miscarriages. Cytogenetic analysis of cultured amniotic fluid cells with GTG banding showed a 46,XX,t(5;16;10;18)(q13;q22;q11.2;q21) karyotype. Parental cytogenetic study revealed that the mother has the same CCR. RBG banding, high resolution banding and fluorescence in situ hybridization (FISH) were used to characterize further and confirm the conventional banding data. No physical abnormalities were shown in the targeted fetal ultrasonography examination. The parents decided to continue the pregnancy. The child is now 2 years old and has neither congenital anomalies nor evidence of delayed psychomotor development. The fetal targeted ultrasound and FISH analysis helped us reassure fetal status.     

Rapid detection of trisomy 21 by gene dosage analysis using quantitative real-time polymerase chain reaction

AIM: Rapid detection of fetal aneuploidy helps inform a mother's choice about the course of her pregnancy. Obtaining results by fluorescent in situ hybridization (FISH) requires more than 24 h, and thus a more rapid method is needed. METHODS: Conventional G-banding and FISH for chromosome 21 were performed for cultured amniocytes. Genomic DNA was extracted from uncultured amniocytes obtained from 23 patients. TaqMan polymerase chain reaction (PCR) primers were designed to amplify the potassium voltage gated channel gene on chromosome 21q22.12 and the ribosomal phosphoprotein gene on 18q21.1. Quantitative real-time PCR was performed for these two gene fragments and the differences of the threshold cycle (Ct) of the two genes (Ct 18-Ct 21) were calculated for each sample. RESULTS: G-banding revealed that 19 patients had a normal karyotype and four had trisomy 21. FISH resulted in one case of a false positive. The Delta Ct values (Ct 18-Ct 21) of trisomy 21 patients were significantly higher than the values of individuals with normal karyotypes (P < 0.001) and there was no overlapping. CONCLUSIONS: Fetal trisomy 21 is rapidly detectable by gene dosage analysis from amniocytes using quantitative real-time PCR.     

Fetal blood chromosome analysis: some new indications for prenatal karyotyping

Prenatal karyotyping using stimulated fetal blood lymphocytes was undertaken in 170 pregnancies between 16 and 36 weeks gestation for the following reasons--mosaicism or marker chromosomes found in amniotic fluid culture; a family history of X-linked mental retardation with fragile Xq28; fetal abnormalities detected ultrasonographically; late booking or amniotic fluid culture failure in patients with advanced age or balanced translocations; and twin pregnancies discordant for a chromosomal anomaly. Forty-one karyotypic abnormalities were detected (24%). These were: 45,X (7 cases), trisomy 13 (5 cases), trisomy 18 (6 cases), trisomy 21 (4 cases), twin pregnancy where one twin had trisomy 21 (1 case), supernumerary marker chromosome (3 cases, one of which occurred in a twin pregnancy), triploidy (3 cases), X-linked mental retardation with fragile site at Xq28 in males (6 cases), fetal erythroleukaemia (3 cases including 2 cases with Turner's), Fanconi's anaemia (1 case), unbalanced chromosome translocation 47,XY+der22,t(11;22) mat (1 case), mos 46,XX18p-/46,XX,-18+i(18q) (1 case), 46,XXdel(2q) (1 case), and 46,XYt(5;17) de novo (1 case). In fetuses at high risk of a chromosome aberration, a rapidly obtained karyotype is helpful and fetoscopy and fetal blood sampling are justified in the second or third trimester.     

Prenatal diagnosis and molecular cytogenetic characterization of chromosome 22q11.2 deletion syndrome associated with congenital heart defects

ObjectiveTo report prenatal diagnosis of 22q11.2 deletion syndrome in a pregnancy with congenital heart defects in the fetus.Case reportA 26-year-old, primigravid woman was referred for counseling at 24 weeks of gestation because of abnormal ultrasound findings of fetal congenital heart defects. The Level II ultrasound revealed a singleton fetus with heart defects including overriding aorta, small pulmonary artery, and ventricular septal defect. Cordocentesis was performed. The DNA extracted from the cord blood was analyzed by multiplex ligation-dependent amplification (MLPA). The MLPA showed deletion in the DiGeorge syndrome (DGS) critical region of chromosome 22 low copy number repeat (LCR) 22-A∼C. Conventional cytogenetic analysis revealed a normal male karyotype. Repeated amniocentesis and cordocentesis were performed. Whole-genome array comparative genomic hybridization (aCGH) on cord blood was performed. aCGH detected a 3.07-Mb deletion at 22q11.21. Conventional cytogenetic analysis of cultured amniocytes revealed a karyotype 46,XY. Metaphase fluorescence in situ hybridization (FISH) analysis on cultured amniocytes confirmed an interstitial 22q11.2 deletion.ConclusionPrenatal ultrasound findings of congenital heart defects indicate that the fetuses are at increased risk for chromosome abnormalities. Studies for 22q11.2 deletion syndrome should be considered adjunct to conventional karyotyping. Although FISH has become a standard procedure for diagnosis of 22q11.2 deletion syndrome, MLPA can potentially diagnose a broader spectrum of abnormalities, and aCGH analysis has the advantage of refining the 22q11.2 deletion breakpoints and detecting uncharacterized chromosome rearrangements or genomic imbalances.     

Chromosomal abnormalities associated with neural tube defects (II): partial aneuploidy

Fetuses with neural tube defects (NTDs) carry a risk of chromosomal abnormalities. The risk varies with maternal age, gestational age at diagnosis, association with other structural abnormalities, and family history of chromosome aberrations. This article provides a comprehensive review of structural chromosomal abnormalities associated with NTDs, such as del(13q), r(13), dup(2p), del(2q), del(1p), del(1q), dup(1q), del(3p), dup(3p), del(3q), dup(3q), del(4p), dup(4p), del(4q), dup(4q), del(5p), del(6p), dup(6q), del(6q), dup(7p), del(7q), dup(8q), del(9p), del(10q), del(11q), dup(11q), dup(12p), dup(14q), del(14q), del(15q), dup(16q), del(18q), r(18), dup(20p), +i(20p), del(22q), del(Xp), and dup(Xq). NTDs may be associated with aneuploidy. Perinatal identification of NTDs should alert one to the possibility of chromosomal abnormalities and prompt a thorough cytogenetic investigation and genetic counseling.     

Microphthalmia with linear skin defects (MLS) syndrome evaluated by prenatal karyotyping, FISH and array comparative genomic hybridization

OBJECTIVE: To explore the utility of comparative genomic hybridization to BAC arrays (array CGH) for prenatal diagnosis of microphthalmia and linear skin defects syndrome. METHODS: We used karyotype analysis, FISH and array CGH to investigate an X;Y translocation. Replication studies were done on cultured amniocytes and lymphoblasts. RESULTS: We describe a severe case of MLS syndrome that presented prenatally with multiple anomalies including cystic hygroma, microphthalmia, intrauterine growth restriction and a complex congenital heart defect. Cytogenetic analysis of amniocytes revealed an unbalanced de novo translocation between chromosomes X and Y [karyotype 46,X,der(X)t(X;Y)(p22.3;q11.2).ish der(X)(DXZ1+,DMD+,KAL-,STS-,SRY-),22q11.2 (Tuple1 x 2)]. MLS diagnosis was made at birth and the prenatal karyotype was confirmed. Replication studies showed the derivative X chromosome was the inactive X. Array CGH confirmed the X and Y imbalances seen in the karyotype and also showed twelve BACs in the MLS region were deleted as a result of the translocation. FISH with BAC clones verified the array findings and placed the X breakpoint in Xp22.2, resulting in the amended karyotype, 46,X,der(X)t(X;Y)(p22.2;q11.2).ish der(X)(DXZ1+,DMD+,KAL-,STS-,SRY-),22q11.2(Tuple1 x 2) arr cgh Xp22.33p22.2(LLNOYCO3M15D10 -->GS1-590J6)x 1,Yq11.222q23(RP11-20H21-->RP11-79J10)x 1. CONCLUSION: The sensitivity of array CGH was valuable in detecting monosomy of the MLS critical region. Array CGH should be considered for the prenatal diagnosis of this syndrome.     

Prenatal diagnosis and molecular cytogenetic characterization of a familial small supernumerary marker chromosome derived from the acrocentric chromosome 14/22

ObjectiveWe present prenatal diagnosis and molecular cytogenetic characterization of a familial small supernumerary marker chromosome (sSMC) derived from the acrocentric chromosome 14/22.Case reportA 40-year-old, gravida 2, para 1, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XY,+mar. Prenatal ultrasound was unremarkable. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed no genomic imbalance. Cytogenetic analysis of the parental bloods revealed a karyotype of 47,XY,inv (9) (p12q13),+mar in the father and a karyotype of 46, XX in the mother. The sSMC was investigated by fluorescence in situ hybridization (FISH) analysis on cultured amniocytes using the CEP 13/21 α-satellite specific gene probe labeled with fluorescein isothiocyanate (FITC) fluorophore and the CEP 14/21 α-satellite specific gene probe labeled with Texas Red fluorophore (Cytocell Inc.). The result showed that the sSMC was derived from the chromosome 14/22, or+mar.ish dic (14/22) (D13Z1/D21Z1-, D14Z1/D22Z1+)[20]. A healthy male baby was delivered at term with no phenotypic abnormality. Quantitative fluorescent polymerase chain reaction (QF-PCR) analysis on parental bloods and the child's peripheral blood was used to exclude uniparental disomy (UPD) (14) and UPD(22).ConclusionFISH analysis is useful for the determination of an sSMC derived from an acrocentric chromosome under the circumstance of no genomic imbalance at amniocentesis. QF-PCR analysis is useful for excluding the possible associated UPD.     

Laparoscopic gonadectomy in a case of a dicentric fluorescent Y-chromosome mosaicism with Turner-like phenotype and virilized external genitalia

In few cases of Turner syndrome the karyotype reveals the presence of an additional Y-bearing cell line, which is referred to as a borderline case of mixed gonadal dysgenesis. We report a 20-year-old woman with primary amenorrhea, virilization and a few Turner stigmata, who revealed rare mosaicism of 45,X/46,X dic (Y; 5)(q12; q11), +5/46,X, der (Y), which was detected by conventional G-banding and multicolor spectral karyotyping. She underwent laparoscopic gonadectomy in which mixed gonadal dysgenesis was found and both gonads were removed. No evidence of gonadoblastoma was noted on the gonads. Virilization improved postoperatively. We recommend gonadectomy via laparoscope in women presenting with Turner-like phenotype, virilization and the presence of a Y chromosome. This report describes the role of cytogenetic and molecular genetic investigations in the definition of mosaicism in Turner syndrome.