无精子症及严重少精子症患者Y染色体AZF微缺失及点突变的研究

目的通过对无精子症和严重少精子症患者Y染色体AZF微缺失的检测,确定AZF微缺失的发生率及高发位点;同时,对正常生育男性、无精子症及严重少精子症患者进行sY254、sY255点突变检测,从分子水平探讨精子发生的机制,建立基因型与表型的关系。方法多重PCR技术对Y染色体上AZF 4个区域内的15个序列标签位点进行微缺失检测,采用SSCP方法进行sY254、sY255点突变检测;结果无精子症和严重少精子症患者Y染色体AZF微缺失率分别为9.80%和9.68%,显著高于少精子症组的3.34%(P<0.05);其中sY152、sY239、sY243、sY254、sY255在Y染色体上的位置相互毗邻,其联合缺失39例,占总缺失率的65.0%,AZFb+AZFd+AZFc联合缺失的有8人,占总缺失的13.3%;本研究中,正常生育男性、无精子症及严重少精子症患者均未发现sY254、sY255的点突变。结论Y染色体AZF微缺失是导致无精子症和严重少精子症的重要因素,sY152、sY239、sY243、sY254、sY255联合缺失是AZF的缺失热点;未发现sY254、sY255点突变。     

不育患者Y染色体AZF微缺失的分析

目的探讨Y染色体上AZF区域微缺失与男性不育的关系。方法采用多重PCR技术,对20例不育患者AZF4个区的l5个序列标签位点（STS）进行了微缺失检测和细胞遗传学检查。结果20例患者中共有3例发现微缺失（15%）。结论AZF微缺失是导致男性不育的重要原因之一,细胞遗传学检查与AZF微缺失无相关性。     

染色体微阵列芯片分析技术应用于产前诊断为关键问题探讨

染色体微阵列芯片分析（CMA）包括比较基因组杂交微阵列（array CGH）和单核苷酸多态微阵列（SNP array）,可以在全基因组范围内高分辨检测染色体的微缺失和微重复,与传统染色体核型分析和荧光原位杂交（FISH）检测相比,具有高通量、高分辨率和高自动化检测的优势,同时可以一次性同步检测许多与出生缺陷和先天性疾病相关的基因组异常,近年来已经开始应用于侵入性产前诊断。回顾近年来多个大样本和多中心的临床试验对CMA技术用于产前诊断的研究结果,借鉴美国妇产科医师协会（ACOG）和母婴医学协会（SMFM）发布的CMA在产前诊断应用中的建议,对CMA在应用过程中如何选择微阵列芯片类型、检测的适用对象和检测的时期、检测结果的解释以及相关的遗传咨询等关键问题进行了详细讨论,并指出CMA在产前诊断应用中面临的机遇和挑战,以及检测前和检测后遗传咨询在实际应用中的重要性和必要性。     

Microdeletions and Microduplications in Patients with Congenital Heart Disease and Multiple Congenital Anomalies

Objective. Multiple genetic syndromes are caused by recurrent chromosomal microdeletions or microduplications. The increasing use of high‐resolution microarrays in clinical analysis has allowed the identification of previously undetectable submicroscopic copy number variants (CNVs) associated with genetic disorders. We hypothesized that patients with congenital heart disease and additional dysmorphic features or other anomalies would be likely to harbor previously undetected CNVs, which might identify new disease loci or disease‐related genes for various cardiac defects. Design. Copy number analysis with single nucleotide polymorphism‐based, oligonucleotide microarrays was performed on 58 patients with congenital heart disease and other dysmorphic features and/or other anomalies. The observed CNVs were validated using independent techniques and validated CNVs were further analyzed using computational algorithms and comparison with available control CNV datasets in order to assess their pathogenic potential. Results. Potentially pathogenic CNVs were detected in twelve of 58 patients (20.7%), ranging in size from 240 Kb to 9.6 Mb. These CNVs contained between 1 and 55 genes, including NRP1, NTRK3, MESP1, ADAM19, and HAND1, all of which are known to participate in cardiac development. Conclusions. Genome‐wide analysis in patients with congenital heart disease and additional phenotypes has identified potentially pathogenic CNVs affecting genes involved in cardiac development. The identified variant loci and the genes within them warrant further evaluation in similarly syndromic and nonsyndromic cardiac cohorts.     

男性不育患者Y染色体微缺失检测意义的探讨

目的:研究男性不育,尤其特发无精和严重少精者与Y染色体微缺失的关系及缺失类型。方法:运用PCR技术对294例男性不育患者进行Y染色体微缺失检测。结果:21例存在Y染色体微缺失,其中16例为AZF(c+d)联合位点缺失(临床表现13例为严重少弱精、3例为无精症),1例为AZF(b+c+d)联合位点缺失(临床表现为无精症),1例为AZFb位点SY143,SY127,SY124,SY134,SY128,SY133联合缺失(临床表现为无精症)。1例为AZFbSY133缺失,2例为AZFbSY127缺失(临床表现均为少弱精症)。结论:Y染色体微缺失多表现为多个位点的联合缺失,可造成生精障碍或阻滞,表现为严重少精或无精症。     

少精症患者Y染色体微缺失基因诊断的研究

目的 建立稳定的少、弱精症患者Y染色体微缺失的基因诊断方法，研究 男性不育与Y染色体位点缺失的相关性。方法选取位于AZE区15个STR微卫星标记分成4组进行多重PCR的检测。结果 90例少弱精患者中，检出7例缺失，占患者的7.8％。其中有3例为单个位点的缺失，有4例为大片断缺失。结论 多重PCR是检测Y染色体微缺失的合适方法，AZEb和AZEc区与少弱精症密切相关。     

A de novo 921 Kb microdeletion at 11q13.1 including neurexin 2 in a boy with developmental delay,deficits in speech and language without autistic behaviors

Microdeletions at 11q13.1 are very rare. At present only two patients with 11q13.1 deletion involving neurexin 2 (NRXN2) have been reported. Both patients exhibited autistic features, which supported the role of NRXN2 in autism pathogenicity. It is currently unknown whether heterozygous deletion of NRXN2 is of high penetrance or if it is sufficient to result in autism behaviors. Here we reported a 2-year-9-month old boy with developmental delay, short stature, significant language delay and other congenital anomalies. In contrast to previously reported cases, the boy did not present with autistic behaviors and did not meet the clinical diagnosis of autism. A de novo 921?kb microdeletion at 11q13.1 was detected by chromosomal microarray analysis (CMA). Whole Exome Sequencing (WES) was also employed for our patient. The deletion was confirmed and no additional pathogenic variants were detected. We compared our patient's genomic information and clinical features with those of two previously reported individuals. Three patients shared similar deleted intervals and had similar clinical features except for autistic behaviors. This study suggested that NRXN2 gene had incomplete penetrance for autistic behavioral phenotype. The finding is of interest for genetic counseling and clinical management to patients with NRXN2 defects.     

FISH Diagnosis of 22q11.2 Deletion Syndrome

The 22q11.2 deletion syndrome is the most common microdeletion syndrome. Although once thought to be separate disorders, cardiac anomalies, abnormal face, thymic hypoplasia, cleft palate, hypocalcemia, and chromosome 22 deletions (CATCH 22); DiGeorge syndrome; velocardiofacial syndrome; and conotruncal anomaly face syndrome are now known to be part of the same 22q11.2 deletion syndrome. Diagnosis of this syndrome is extremely challenging because of wide variability in phenotypic presentations. When the deletion is suspected, genetic testing is typically ordered. Conventional karyotyping is only capable of detecting a small percentage of chromosome deletions. However, fluorescence in situ hybridization (FISH) is capable of detecting many deletions and microdeletions. This article discusses the pathophysiology and presentation of chromosome 22q11.2 deletion syndrome. The use of FISH as a diagnostic tool is also described, including the FISH process, its use, and its accuracy and reliability in the diagnosis of chromosome 22q11.2 deletion syndrome in the fetus and/or newborn.     

MLPA analysis in 30 Sotos syndrome patients revealed one total NSD1 deletion and two partial deletions not previously reported

Sotos syndrome (MIM #117550) is an autosomal dominant condition characterized by pre and postnatal overgrowth, macrocephaly and typical facial gestalt with frontal bossing, hypertelorism, antimongoloid slant of the palpebral fissures, prominent jaw and high and narrow palate. This syndrome is also frequently associated with brain, cardiovascular, and urinary anomalies and is occasionally accompanied by malignant lesions such as Wilms tumour and hepatocarcinoma. The syndrome is known to be caused by mutations or deletions of the NSD1 gene.To detect both 5q35 microdeletions and partial NSD1 gene deletions we screened 30 Brazilian patients with clinical diagnosis of Sotos syndrome by multiplex ligation dependent probe amplification.We identified one patient with a total deletion of NSD1 and neighbouring FGFR4, other with missing NSD1 exons 13-14 and another with a deletion involving FGFR4 and spanning up to NSD1 exon 17. All deletions were de novo. The two NSD1 partial deletions have not been previously reported.The clinical features of the three patients included a typical facial gestalt with frontal bossing, prominent jaw and high anterior hairline; macrocephaly, dolichocephaly, large hands; neonatal hypotonia and jaundice. All presented normal growth at birth but postnatal overgrowth. Two patients with NSD1 and FGFR4 gene deletions presented congenital heart anomalies.     

3q29 interstitial microdeletion syndrome: An inherited case associated with cardiac defect and normal cognition

An inherited, interstitial subtelomere deletion of approximately 1.3–1.4 Mb at 3q29 was identified in a patient and his father utilizing BAC array comparative genomic hybridization (a-CGH). The imbalance was located within the common 3q29 microdeletion syndrome region and shared the distal breakpoint with prior published cases. However, our patient was developmentally normal at 6 months of age and his father is a functional adult, who had mild developmental delay in childhood. They presented with congenital cardiac defects including patent ductus arteriosus. In addition, the patient had subvalvular aortic stenosis and his father had pulmonic stenosis. These defects were not present in most of the previously reported 3q29 microdeletion cases. This case expands the phenotypic findings associated with 3q29 microdeletion syndrome, suggesting an association with cardiac defect. It also raises the possibility of normal cognition in adulthood.