染色体微阵列分析技术在210例发育迟缓/智力低下患儿中的应用

目的探讨染色体微阵列分析技术(CMA)在检查核型分析未见异常的发育迟缓/智力低下(DD/ID)患儿方面的应用价值。方法选取210例DD/ID伴或不伴其他异常患儿,分为2组:单纯性DD/ID组( n =90),复杂性DD/ID组( n =120例,合并癫痫23例、头颅磁共振异常36例、心血管系统19例、多发结构畸形42例)。提取其外周血DNA,采用CGXv1.18-plex基因芯片进行全基因组拷贝数变异(CNVs)检测,查询国际病理性CNV数据库(ClinVar、DECIPHER、OMIM等)、DGV数据库,检索PubMed数据库相关文献,对CNVs致病性进行分析。结果在210例DD/ID患儿中检出83例染色体拷贝数异常,检出率为39.5%。其中,检出已知致病的常见微缺失/微重复综合征66例;罕见综合征1例(Kleefstra综合征)。可疑致病变异的微缺失/微重复9例,可能良性变异1例,临床意义不明6例。结论 CMA可以明显提高DD/ID患儿遗传学病因的诊断率,对于患儿的治疗及其父母的再生育具有重要的指导意义。因此可以作为DD/ID患儿的一线诊断方法。

Association between TLR7 copy number variations and hepatitis B virus infection outcome in Chinese

AIM To explore whether copy number variations (CNVs) of toll-like receptor 7 (TLR7) are associated with susceptibility to chronic hepatitis B virus (HBV) infection. METHODS This study included 623 patients (495 males and 128 females) with chronic hepatitis B virus infection (CHB) and 300 patients (135 females and 165 males) with acute hepatitis B virus infection (AHB) as controls. All CHB patients were further categorized according to disease progression after HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). Copy numbers of the TLR7 gene were measured using the AccuCopy method chi(2) tests were used to evaluate the association between TLR7 CNVs and infection type. P values, odds ratios, and 95% confidence intervals (CIs) were used to estimate the effects of risk. RESULTS Among male patients, there were significant differences between the AHB group and CHB group in the distribution of TLR7 CNVs. Low copy numberof TLR7 was significantly associated with chronic HBV infection (OR = 0.329, 95% CI: 0.229-0.473, P > 0.001). Difference in TLR7 copy number was also found between AHB and CHB female patients, with low copy number again associated with an increased risk of chronic HBV infection (OR = 0.292, 95% CI: 0.173- 0.492, P < 0.001). However, there were no significant differences in TLR7 copy number among the three types of chronic HBV infection (CHB, liver cirrhosis, or hepatocellular carcinoma). In addition, there was no association between TLR7 copy number and titer of the HBV e antigen. CONCLUSION Low TLR7 copy number is a risk factor for chronic HBV infection but is not associated with later stages of disease progression.

Autism spectrum disorder model mice: Focus on copy number variation and epigenetics

Autism spectrum disorder(ASD) is gathering concerns in socially developed countries. ASD is a neuropsychiatric disorder of genetic origin with high prevalence of 1%–2%. The patients with ASD characteristically show impaired social skills. Today, many genetic studies identify numerous susceptible genes and genetic loci associated with ASD. Although some genetic factors can lead to abnormal brain function linked to ASD phenotypes, the pathogenic mechanism of ASD is still unclear. Here, we discuss a new mouse model for ASD as an advanced tool to understand the mechanism of ASD.