应用GeXP遗传分析系统检测病毒性脑炎患儿脑脊液中的人类鼻病毒

目的探讨儿童脑炎与鼻病毒的关系以及GeXP多重基因表达遗传分析系统在病毒性脑炎患儿脑脊液人类鼻病毒检测方面的应用价值。方法选择2012年1~12月因发热抽搐等症状就诊于汕头大学医学院第二附属医院儿科重症监护室的患儿脑脊液140份,应用GeXP遗传分析系统对脑脊液标本进行包括人类鼻病毒在内的常见呼吸道病毒筛查,巢式RT-聚合酶链反应(PCR)扩增鼻病毒阳性标本,并对扩增产物进行核酸序列测定和同源性比对。结果 GeXP遗传分析系统共检测出6份鼻病毒阳性标本,经巢式RT-PCR扩增、核酸序列测定和同源性比对,结果为鼻病毒C型4份,与GenBank数据库参考序列同源性为95.8%~98.3%。鼻病毒A型和B型各1份,与参考序列同源性分别为96.0%和99.0%。结论鼻病毒是引起儿童脑炎的病原之一,GeXP遗传分析系统为病毒性脑炎的病原学研究提供快速高通量的检测。     

白血病随机扩增多态DNA分析及其临床意义

为探讨随机扩增多态ＤＮＡ（ＲＡＰＤ）技术分析急性白血病基因组多态性特征及其临床意义，采用１０种随机引物对急性白血病进行ＲＡＰＤ分析和选择特征引物进行临床观察。结果显示：急性淋巴白血病与急性髓细胞白血病各自有特征的ＲＡＰＤ标记，可以在ＤＡＮ判别各类型白血病。ＲＡＰＤ标记可能用于白血病的基因分型，微小残留病检测等研究。     

CLINICAL AND GENETIC ANALYSIS OF THREE FAMILIES WITH FAMILIAR AMYLOID POLYNEUROPATHY

Objective To study the clinical and genetic features of familiar amyloid polyneuropathy （FAP）.
Methods Three families of suspected FAP in China mainland and Macau were investigated on aspects of clinical manifestations, histological features, and gene analysis.
Results All the 3 families had the clinical features of sensory and motor polyneuropathies, and notable vegetative nerve involvements. Affected cases of one family had ultrasound proved cardiomyopathy. Histological studies showed amyloid deposition in all the biopsy tissues of the affected cases of the 3 families, and anti-transthyretin antisera staining was positive in 3 cases of one family. Gene analysis confirmed that mutation types were amyloidogenic transthyretin （ATTR） Val30Met, Phe33Val, and Gly67Glu in the 3 families respectively. The ATTR Gly67Glu family had a shorter survival time due to the heart involvement compared with the other 2 families.
Conclusion FAP is an autosomal dominant inherited disease, with its clinical manifestations related to the type of genetic mutation.     

EIF2S3 基因变异致MEHMO 综合征2 例报告并文献复习

目的探讨MEHMO综合征的临床特征与遗传学特点。方法回顾分析2例确诊MEHMO综合征患儿的临床资料,并复习相关文献。结果两例患儿均为男性。例1于2岁3个月就诊,表现为癫痫发作、智力低下、进行性痉挛性四肢瘫、小头畸形、面部畸形、身材矮小和隐睾等。例2于3月龄就诊,4个月15天龄死亡,表现为反复低血糖、小头畸形和小阴茎,癫痫状态持续、难治。两例患儿均存在乳酸酸中毒,头颅MRI均显示胼胝体薄。例1患儿EIF 2 S 3基因存在c.137C>T(p.Thr 46 Ile)错义变异,例2患儿EIF 2 S 3基因存在c.1391_c.1394delCAAT(p.T 464 Tfs*5)移码变异。这2种变异在人类基因变异数据库(HGMD)等均未见收录,美国医学遗传学与基因组学(ACMG)基因变异解读指南均评定为致病性变异。检索到国外文献5篇,包含18例患者,有5个EIF 2 S 3基因变异位点,1个移码变异和4个错义变异,均为半合子变异。移码变异患者表现出智力障碍、癫痫发作、生殖器发育不全、小头畸形、肥胖、发育迟缓和低血糖等MEHMO综合征的全部重要表型,而错义变异患者表现部分表型且症状较轻。结论MEHMO综合征存在一定的基因型-表型相关性。首次报道2例中国人群MEHMO综合征,并发现2个新的EIF 2 S 3基因变异位点。     

Genetic analysis and serum level of cartilage oligomeric matrix protein in patients with pseudoachondroplasia

Background Pseudoachondroplasia （PSACH） is an autosomal-dominant osteochondrodysplasia due to mutations in the gene encoding cartilage oligomeric matrix protein （COMP）.Clinical diagnosis of PSACH is based primarily on family history, physical examination, and radiographic evaluation.There is evidence that decreased serum COMP concentration may serve as a diagnostic marker in PSACH.Here, we investigated the role of this gene and the serum COMP concentration in Chinese patients with PSACH.Methods A family with three patients and a sporadic case were recruited.Genomic and phenotypic data were recorded.The diagnosis of PSACH was made on the base of clinical evaluation.The genomic DNA was extracted from peripheral blood leukocytes.The 8-19 exons and flanking intron-exon boundary sequences of COMP were amplified by polymerase chain reaction （PCR） and screened for mutation by direct DNA sequencing.Serum COMP concentrations of 4 patients and age-compatible control group of 20 unrelated healthy subjects were analyzed on the basis of an ELISA Kit for human cartilage oligomeric matrix protein.Results A deletion （c.1447-1455del） was identified in exon 13 in the sporadic case.The mean serum COMP concentrations of four patients （3.12±2.28） were significantly lower than those of control group （10.86±2.21, P 〈0.05）.There was no overlap in the distribution of serum COMP concentration between PSACH patients and controls.Conclusions Mutations in COMP gene are responsible for the PSACH.Serum COMP concentration may be suggested as an additional diagnostic marker to aid clinical findings in suspected cases of PSACH.     

云南边境地区禽流感H5N1亚型病毒NS基因进化分析

目的 阐明云南边境地区禽流感H5N1亚型病毒NSl、NS2基因变异特征及遗传进化关系。方法 在云南边境地区采集境外家禽和野生鸟类棉拭子样品,经H5N1亚型特异性多重RT-PCR检测,阳性样品对病毒NS基因进行扩增,克隆Z至pMDl8一T载体测序,获得NSl、NS2基因序列,并与已知参考毒株序列进行序列比对及系统发育分析。结果 自1240份样品中检出H5N]亚型阳性样品71份,阳性率为5．72％;30份代表性阳性样品病毒NS基因测序获得17种序列,存在3个不同进化(亚)分支(I一1、I一2、Ⅱ);NSl／NS2基因与病毒血凝素(HA)基因呈现不同进化关系;NSl蛋白涉及核定位信号区、RNA结合区、效应区及其他致病性相关的关键性氨基酸位点存在替代或突变。结论 云南边境地区H5N1亚型病毒NSl／NS2基因具有遗传差异,2010年以来NS基因进化分支I一2、Ⅱ已成为当地流行的优势毒株。     

一个多发性染色体畸变家系的细胞遗传学分析

对一个染色体畸变家系细胞遗传学研究发现，先证者及其父的外周血淋巴细胞染色体有多发性染色体裂隙，并伴有断裂、缺失、易位、三射体和四射体等多种染色体畸变。两者的染色体裂隙和断裂数目的比较分析表明：先证者及其父的各对应染色体的裂隙数目密切相关。先证者３６４个染色体裂隙区带与其父的裂隙区带相同，占前者全部裂和断裂数的８１．８０％。两者的裂隙和断裂区带发生在常见的脆性位点的分别为３４．１６％和３２．３０％，     

概率原理在遗传分析题中的应用

概率是指某事件发生的可能性的大小,计算概率有2个重要的原理:乘法原理和加法原理。阐述了概率的原理在遗传分析题中的应用。