Abstract：
BACKGROUND: A retrospective analysis using chromosomal microarray in syndromic patients with intellectual disability from genetic clinics of a tertiary healthcare center in India was conducted.
OBJECTIVE: To identify the spectrum of chromosomal abnormalities detected on microarray analysis.
METHODS: Cases were identified among those with intellectual disability with dysmorphism attending genetic clinics of a tertiary care center.
METHODS: All patients attending genetic clinics over a 3-year period were analyzed. Clinical profile and baseline investigations were noted on a predesigned proforma. Among the 65 studied cases, there were 12 cases suggested to be having Prader-Willi syndrome (PWS), 27 cases with DiGeorge/velocardiofacial syndrome (DGS), and 1 case with Williams-Beuren syndrome (WBS). These were detected by fluorescent in situ hybridization (FISH) analysis with specific probes and were excluded from the final analysis. Chromosomal microarray analysis (CMA; single-nucleotide polymorphism-based array-comparative genomic hybridization) was performed as per the clinical indication in selected patients with dysmorphism, microcephaly, mental retardation, and/or multiple malformations. These patients had a negative result on FISH analysis.
RESULTS: In suspected patients with PWS, FISH and methylation testing confirmed six cases to be really PWS. FISH also detected five cases of DGS and one case of WBS. These were excluded from the final analysis. Among the 18 cases tested by CMA, in 13 patients, abnormalities with potential clinical significance were identified. Genetic counseling was done in all these cases. Prenatal diagnosis was done in one family.
CONCLUSIONS: In cases with dysmorphism with or without mental retardation or cardiac defect, advanced studies such as CMA can lead to a definitive diagnosis. Genetic counseling is mandatory in all these cases and a prenatal diagnosis is also feasible in selected families.
OBJECTIVE: To identify the spectrum of chromosomal abnormalities detected on microarray analysis.
METHODS: Cases were identified among those with intellectual disability with dysmorphism attending genetic clinics of a tertiary care center.
METHODS: All patients attending genetic clinics over a 3-year period were analyzed. Clinical profile and baseline investigations were noted on a predesigned proforma. Among the 65 studied cases, there were 12 cases suggested to be having Prader-Willi syndrome (PWS), 27 cases with DiGeorge/velocardiofacial syndrome (DGS), and 1 case with Williams-Beuren syndrome (WBS). These were detected by fluorescent in situ hybridization (FISH) analysis with specific probes and were excluded from the final analysis. Chromosomal microarray analysis (CMA; single-nucleotide polymorphism-based array-comparative genomic hybridization) was performed as per the clinical indication in selected patients with dysmorphism, microcephaly, mental retardation, and/or multiple malformations. These patients had a negative result on FISH analysis.
RESULTS: In suspected patients with PWS, FISH and methylation testing confirmed six cases to be really PWS. FISH also detected five cases of DGS and one case of WBS. These were excluded from the final analysis. Among the 18 cases tested by CMA, in 13 patients, abnormalities with potential clinical significance were identified. Genetic counseling was done in all these cases. Prenatal diagnosis was done in one family.
CONCLUSIONS: In cases with dysmorphism with or without mental retardation or cardiac defect, advanced studies such as CMA can lead to a definitive diagnosis. Genetic counseling is mandatory in all these cases and a prenatal diagnosis is also feasible in selected families.
摘要：
背景：使用染色体微阵列对印度三级医疗保健中心遗传诊所的智力障碍综合征患者进行了回顾性分析。
目的：鉴定微阵列分析中检测到的染色体异常谱。
方法：在三级护理中心的遗传诊所就诊的智障患者中发现了病例。
方法：分析了在3年期间参加遗传诊所的所有患者。在预先设计的形式上记录了临床概况和基线调查。在研究的65个案例中，有12例建议患有Prader-Willi综合征（PWS），DiGeorge/心面综合征（DGS）27例，1例Williams-Beuren综合征(WBS)。这些通过使用特异性探针的荧光原位杂交(FISH)分析来检测,并且从最终分析中排除。染色体微阵列分析（CMA；基于单核苷酸多态性的阵列-比较基因组杂交）根据临床指征在选定的畸形患者中进行，小头畸形,智力迟钝,和/或多个畸形。这些患者的FISH分析结果为阴性。
结果：在疑似PWS患者中，FISH和甲基化检测证实了6例确实是PWS。FISH还检测到5例DGS和1例WBS。这些被排除在最终分析之外。在CMA测试的18例病例中，在13名患者中，确定了具有潜在临床意义的异常。在所有这些情况下都进行了遗传咨询。在一个家庭中进行产前诊断。
结论：在有或没有精神发育迟滞或心脏缺陷的畸形患者中，诸如CMA之类的高级研究可以导致明确的诊断。在所有这些情况下，遗传咨询是强制性的，在选定的家庭中，产前诊断也是可行的。
目的：鉴定微阵列分析中检测到的染色体异常谱。
方法：在三级护理中心的遗传诊所就诊的智障患者中发现了病例。
方法：分析了在3年期间参加遗传诊所的所有患者。在预先设计的形式上记录了临床概况和基线调查。在研究的65个案例中，有12例建议患有Prader-Willi综合征（PWS），DiGeorge/心面综合征（DGS）27例，1例Williams-Beuren综合征(WBS)。这些通过使用特异性探针的荧光原位杂交(FISH)分析来检测,并且从最终分析中排除。染色体微阵列分析（CMA；基于单核苷酸多态性的阵列-比较基因组杂交）根据临床指征在选定的畸形患者中进行，小头畸形,智力迟钝,和/或多个畸形。这些患者的FISH分析结果为阴性。
结果：在疑似PWS患者中，FISH和甲基化检测证实了6例确实是PWS。FISH还检测到5例DGS和1例WBS。这些被排除在最终分析之外。在CMA测试的18例病例中，在13名患者中，确定了具有潜在临床意义的异常。在所有这些情况下都进行了遗传咨询。在一个家庭中进行产前诊断。
结论：在有或没有精神发育迟滞或心脏缺陷的畸形患者中，诸如CMA之类的高级研究可以导致明确的诊断。在所有这些情况下，遗传咨询是强制性的，在选定的家庭中，产前诊断也是可行的。
