Mild dopa-responsive dystonia in heterozygous tyrosine hydroxylase mutation carrier: Evidence of symptomatic enzyme deficiency?

We present a case of mild, adult-onset dopa-responsive dystonia (DRD) with a heterozygous mutation in the tyrosine hydroxylase (TH) gene. We propose that this genetic state may have led to partial enzyme deficiency. Future studies should attempt to identify and characterize the phenotype of other patients with single TH variants.     

G6PD比值法检测葡萄糖-6-磷酸脱氢酶基因突变女性杂合子影响因素的研究

目的确定G6PD/6PGD比值法在检测葡萄糖-6-磷酸脱氢酶缺乏的女性杂合子时的最佳实验条件,提高对葡萄糖-6-磷酸脱氢酶缺乏的女性杂合子的检出率。方法(1)应用突变特异性扩增系统确定女性杂合子的基因突变型。(2)G6PD/6PGD定量比值法。结果根据试验结果进行统计分析及ROC曲线得出最佳实验条件为孵育温度为37℃,底物浓度为0.78mmol/LG6PNa2及0.195mmol/LNADP ,反应时间为10min。结论G6PD/6PGD比值法在最佳实验条件下,能大大提高对G6PD基因突变女性杂合子的检出率。     

斑状角膜营养不良一家系发现新的复合杂合突变

目的 明确一个中国斑状角膜营养不良(MCD)家系中致病基因及其突变的类型及组织病理学改变.方法 对行穿透性角膜移植术后获得的先证者角膜进行光镜和透射电子显微镜检查.收集此家系11个成员的外周血,提取DNA;合成特异性引物,利用聚合酶链式反应(PCR)扩增CHST6基因的编码区;PCR产物进行直接测序和限制性内切酶消化分析.选取100个无关健康个体作为对照.结果 组织特殊染色显示胶性铁染色阳性.透射电子显微镜下观察,可见滑面内质网扩张,胞质空泡化,有细颗粒物质.CHST6基因编码区进行突变检测发现,此家系3个患者CHST6基因第3个外显子存在一个复合杂合突变(Q298X和Y358H),其中第892位碱基C→T,导致第298位的谷氨酰胺变成终止密码子;第1072位碱基 T→C,导致第358位的酪氨酸被组氨酸取代.6个表型正常的个体均为杂合子,而在100个无血缘关系的健康个体中没有检测到突变.结论 确定了两个新的突变导致了该家系CHST6基因功能的丧失,引起MCD.该复合杂合突变在国内外为首次报道.     

汉族肥胖儿童黑皮质素4受体基因筛查

目的探讨肥胖儿童黑皮质素4受体(MC4R)的突变频率及其与临床生化指标改变的关系。 方法浙江大学医学院附属儿童医院等单位于2004—2005年,对200例肥胖及100例正常体重儿童,利用PCR及基因测序技术进行MC4R基因筛查,同时对200例肥胖儿童进行生化检测和口服葡萄糖耐量试验。 结果(1)200例肥胖儿童中检出杂合子错义突变、无义突变3例;100例对照组中未检出突变;Val103Ile基因多态性在两组中分别有6例、2例。肥胖组中发现了3个新的杂合子突变位点Val166Ile、Cys277Stop、Arg310Lys;肥胖组和对照组中同时检测到新的杂合子变异Leu23Arg。(2)MC4R突变组和非突变组的肥胖儿童BMI、ALT、AST、TG、CHO、WBISI比较均无统计学意义(P>0.05)。 结论(1)首次在汉族儿童人群中发现了MC4R基因3个新的杂合子突变位点(Val166Ile、Cys277Stop、Arg310Lys)。(2)Leu23Arg可能是汉族人群MC4R的基因多态性。     

3种少见α地中海贫血点突变杂合取合予的临床特征

目的：了解3种少见α地中海贫血点突变[血红蛋白Constants Spring （Hb CS）,血红蛋白Westmead（Hb WS）和血红蛋白Quong Sze（Hb QS）]杂合子与双重杂合子的临床特征。方法：收集135例上述3种α-地中海贫血点突变的杂合子与双重杂合子患者和正常对照男女各20例,进行血常规参数分析、血红蛋白分析、等位基因特异性寡核苷酸探针反向斑点杂交方法（RDB）和多重跨越断裂点聚合酶链反应（PCR）方法检测基因型。结果：杂合子组、Hb CS和Hb WS双重杂合子（αCSα/αWSα）组均无临床表现,但Hb QS杂合子（αQSα/αα）组的红细胞平均体积（MCV）和红细胞平均血红蛋白（MCH）值小于其余杂合子组（P＜0.05）。Hb CS和Hb QS双重杂合子（αCSα/αQSα）组有轻微的临床表现,MCV和MCH值低于Hb CS杂合子和Hb WS杂合子组（P＜0.05）。结论：Hb CS杂合子组和Hb WS杂合子组表现为静止型地中海贫血,Hb QS杂合子组更接近轻型地中海贫血。双重杂合子表型多样,Hb CS和Hb WS双重杂合子表现接近于静止型地中海贫血,而Hb CS和Hb QS双重杂合子表现类似中间型α地中海贫血（Hb H病）,在遗传咨询中需注意。     

Factors that influence parents’ experiences with results disclosure after newborn screening identifies genetic carrier status for cystic fibrosis or sickle cell hemoglobinopathy

Objective

Newborn screening (NBS) identifies genetic carriers for sickle cell hemoglobinopathy and cystic fibrosis. We aimed to identify factors during initial NBS carrier results disclosure by primary care providers (PCPs) that influenced parents’ experiences and reactions.

Methods

Open-ended responses from telephone interviews with 270 parents of carriers were analyzed using mixed-methods. Conventional content analysis identified influential factors; chi-square tests analyzed relationships between factors and parent-reported reactions.

Results

Parents reported positive (35%) or negative (31%) reactions to results disclosure. Parents’ experiences were influenced by specific factors: content messages (72%), PCP traits (47%), and aspects of the setting (30%). Including at least one of five specific content messages was associated (p < 0.05) with positive parental reactions; omitting at least one of four specific content messages was associated (p < 0.05) with negative parental reactions. Parents reported positive reactions when PCPs avoided jargon or were perceived as calm. Parents reported negative reactions to jargon usage and results disclosure by voicemail.

Conclusion

Parents identified aspects of PCP communication which influenced their reactions and results disclosure experiences.

Practice implications

Our findings suggest ways PCPs may improve communication of carrier results. PCPs should provide specific content messages and consider how their actions, characteristics, and setting can influence parental reactions.     

Human leukocyte antigen class II alleles and natural history of HPV 2/27/57-induced common warts

Epidemiological studies have demonstrated an association between HLA-DQB1*03 alleles and the risk of cervical cancer induced by human papillomavirus (HPV). As persistence of HPV infection is required for developing cervical cancer, we wanted to elucidate the role of HLA-class II allele polymorphisms in the persistence of common warts induced by HPV 2, HPV 27 or HPV 57. Therefore, we determined the distribution of HLA-DQA1, -DQB1, and -DRB1 alleles in 71 patients presenting with HPV 2/27/57-induced common warts which had persisted for at least 18 months as well as in 92 individuals who had never suffered from common warts or whose warts had healed in less than 18 months. Among patients with long-lasting warts, the carriership frequencies and allele frequencies of DQA1*0301, DQB1*0301, DRB1*07 and DRB1*09 were higher, and the allele frequencies of DQA1*0501, DQB1*0603, DRB1*01 and DRB1*03 were lower. Statistically significant differences (Bonferroni adjusted Fishers exact test) were found for carriership frequency of DQA1*0301 (46.5 vs 21.7%, P=0.013) and for carriership frequency (18.3 vs 1.1%, P=0.0015) and allele frequency (12 vs 0.5%, P=0.000013) of DQB1*0301. A greater proportion of patients with long-lasting warts than of subjects without persistent warts were homozygous at the DQA1 (14.1 vs 6.5%) and DQB1 (16.9 vs 8.6%) gene loci. These results suggest that the natural history of cutaneous HPV 2/27/57-induced common warts may be modulated by allele polymorphisms at the HLA-DQA1 and HLA-DQB1 gene loci.     

血清铜蓝蛋白检测在肝豆状核变性及其携带者中的临床意义

目的肝豆状核变性(hepatolenticular degeneration)又称为Wilson病(Wilson’s disease,WD)。目前对于铜蓝蛋白在WD、WD携带者及病毒性肝炎的诊断价值尚不一致。文中探讨检测血清铜蓝蛋白在WD、WD携带者和病毒性肝炎中的临床意义,研究WD携带者的临床表现和铜代谢规律。方法确诊的WD患者60例,WD携带者30例,合并病毒性肝炎的WD携带者2例,病毒性肝炎患者20例,健康对照者20例。对所有入组者进行病史采集、临床神经系统检查,检测血清铜蓝蛋白水平以及铜代谢指标检查,包括脑脊液铜、血清铜、青霉胺排铜试验前后24 h尿铜。同时进行神经影像学、腹部B超、肝功能、肝炎标志物检查。结果 WD患者铜蓝蛋白水平低于健康人,排铜试验后尿铜显著高于健康人。WD携带者铜蓝蛋白异常者高达73%,其铜蓝蛋白水平介于健康人和WD患者之间。合并病毒性肝炎的WD携带者铜蓝蛋白水平低于0.1 g/L且随肝功能波动,其尿铜略高于健康人,排铜试验后尿铜高于健康人。单纯病毒性肝炎患者铜蓝蛋白水平仅轻度降低。结论血清铜蓝蛋白水平有助于鉴别WD、WD携带者和其他肝病。病毒性肝炎多导致铜蓝蛋白水平轻度异常;WD携带者合并病毒性肝炎时,铜蓝蛋白水平显著下降。WD携带者的铜蓝蛋白水平常介于健康人和WD患者之间,可作为WD携带者的诊断依据。WD携带者存在轻微铜代谢异常,但无临床症状,不需进行排铜治疗。     

血友病A携带者检测与产前诊断

目的 建立简便、快速的血友病A携带者检测与产前诊断体系。方法 用PCR方法直接检测FⅧ内含子22倒位或对FⅧ基因内的BclⅠ位点、内含子13和22中STR和FⅧ基因外的DXS52（ST14）位点的多态性进行遗传连锁分析。结果 应用内含子22例位的直接诊断率为47．6％;Bcl Ⅰ位点的可诊断率为27．8％;内含子13和22中STR的可诊断率分别为28．6％及29．4％;DCS52的可诊断率为81．3％;综合应用直接诊断和间接遗传连锁分析,对21个家系进行检测,可诊断率为94．7％。结论 血友病A的携带者检测与产前诊断可先进行内含子22倒位的检测,若结果为阳性即可作出诊断;若内含子22例位的检测结果为阴性,则可利用FⅧ基因内、外的多个位点多态性结果进行遗传连锁分析,以作出最终的诊断。     

凝血因子V169G→A基因突变的研究分析

目的 研究分析中国新疆地区健康人群中FV1691G→A基因突变的发生率。方法 凝血因子V(coagulation factor V)在凝血过程中是一种重要的辅因子,其基因中一个点突变1691G→A,使它对抗凝血系统中的一种血浆蛋白质C(APC)的失活作用而产生抗性,从而使血栓发生风险增大。应用多聚酶链反应-限制性片段长度多态性分析(PCR-RFLP),对新疆地区98例汉族、67例维吾尔族和54例哈萨克族健康个体进行研究分析。结果 哈萨克族人群中检出2例FV Leiden 1691G→A突变杂合子;汉族和维吾尔族人群中均未发现该突变类型。结论 中国新疆地区哈萨克族人群中存在FV Leiden基因突变,而汉族和维吾尔族人群中未检测到该类型突变,FV Leiden的发生存在着地区、种族差异,FV Leiden突变可能不是新疆地区人群静脉血栓(VT)发病的主要危险因素。