Screening of pathogenic genes in Chinese patients with arrhythmogenic right ventricular cardiomyopathy

Background Arrhythmogenic right ventricular cardiomyopathy （ARVC） is a heritable cardiac disease predominantly caused by mutations in desmosomal protein genes. Previous genetic analyses of the Chinese ARVC population are limited to small size and restriction to a single gene. This study was aimed to investigate the genotype in a large series of Chinese patients with ARVC through comprehensively screening nine ARVC-causing genes. Methods A total of 100 unrelated ARVC patients and 300 age, gender and ethnicity matched healthy controls were genetically tested with multiplexing targeted resequencing for nine previously reported ARVC-causing genes, including plakophilin-2, desmoplakin, desmoglein-2, desmocollin-2, plakoglobin, transforming growth factor beta-3, transmembrane protein 43, desmin and Lamin A/C. Results Fifty-nine mutations were identified in 64% of the patients, among which, 93% were located in desmosomal protein genes. Plakophilin-2 mutations accounted for 54% of the total and 58% of the desmosomal mutations, with a truncating mutation type making up about 2/3 of the plakophilin-2 mutations. Only four mutations were found in nondesmosomal genes; two in transmembrane protein 43 and two in transforming growth factor beta-3. Two of them （one of each gene） appeared as single missense mutations. No mutation was identified in desmin or Lamin A/C. Multiple mutations were found in 23% of the patients, with plakophilin-2 being found in 57% of the multi-mutation carriers. Conclusions Plakophilin-2 was the most common gene mutation that was identified in Chinese ARVC patients. Nondesmosomal genes should be added to desmosomal protein genes when performing molecular genetic screening in patients with suspected ARVC.     

Molecular Characterization of Drug-Resistant Beijing Family Isolates of Mycobacterium Tuberculosis from Tianjin,China

Objective Tuberculosis remains a severe public health issue, and the Beijing family of mycobacterium tuberculosis （M. tuberculosis） is widespread in East Asia, especially in some areas in China, like Beijing and Tianjin. This study aimed at determining the mutation patterns of drug-resistant Beijing strains of M. tuberculosis isolated from Tianjin, China. Methods A total of 822 M. tuberculosis isolates were screened for drug resistance by an absolute concentration method and the genotype was identified by PCR. 169 drug-resistant isolates of the Beijing family were analyzed for the potential mutations in the rpoB, katG, inhA promoter region and in rpsL, rrs and embB genes, which are associated with resistance to rifampin （RFP）, isoniazid （INH）, streptomycin （SM） and ethambutol （EMB） respectively by PCR and DNA sequencing. Results Fifty-eight out of 63 RFP-resistant isolates were found to carry the mutations within the 81-bp RFP resistance determining region （RRDR） of the rpoB gene and the most frequent mutations occurred at codon 531 （44.4%）, 526 （28.6%）, and 516 （7.9%） respectively. 16 mutation pattems affecting 12 different codons around the RRDR of rpoB were found. Of 116 INH-resistant isolates, 56 （48.3%） had the mutation of katG 315 （AGC→ACC） （Ser→Thr）, 3 （2.6%） carried S315N （AGC→AAC） and 27 （16.0%） had the mutation of inhA-15A→T. 84 out of 122 SM-resistant isolates （68.9%） displayed mutations at the codons 43 or 88 with AAG→AGG （Lys→Arg） of the rpsL gene and 22 （18.0%） with the mutations at positions 513A→C, 516C→T or 905 A→G in the rrs gene. Of 34 EMB-resistant isolates, 6 had mutation with M306V （ATG→GTG）, 3 with M306I （ATG→ATT）, 1 with M306I （ATG→ATA）, 1 with D328Y （GAT→TAT）, 1 with V348L （GTC→CTC）, and 1 with G406S （GGC→AGC） in the embB gene. Conelusion These novel findings extended our understanding of resistance-related mutations in the Beijing strains of M. tuberculosis and may provide a scientific basis for development of new strategies for diagnosis and control of tuberculosis in China and other countries where Beijing strains are prevalent.     

Original article ：Identification of seven novel mutations in the factor Ⅷ gene in 18 unrelated Chinese patients with hemophilia A

Background Hemophilia A （HA） is an X-linked inherited bleeding disorder caused by decreased activity of factor Ⅷ（FⅧ） due to heterogenous mutations in the FⅧ coding gene （F8）. The type of mutation plays an important role in the FVIII inhibitor formation. To date, several studies on the spectra of F8 defects have been performed in Western populations, but similar studies in Asian races are scarce. Here, we reported the distribution of the F8 gene mutations in 18 unrelated Chinese patients with HA. Methods Intron 22 and intron 1 inversions in the F8 gene were screened in 158 unrelated patients with HA using a long-distance PCR and multiplex PCR method. Direct sequencing of the coding region of the F8 gene was used to identify the mutations responsible for HA in 18 unrelated Chinese HA patients who were negative for intron 22 and intron 1 inversions; sequences were compared with the HAMSTERS database. A clotting method was used to assay the FⅧ activity level and the Bethesda assay was used to detect the FⅧ inhibitor. Results A total of 18 different HA F8 mutations were identified, seven of which were described for the first time. These novel mutations included five small deletions, one point mutation and one small insertion. One novel mutation （4382-3 AC deletion） was associated with inhibitor development. Conclusion These data extend our insight into the mechanisms by which novel amino acid mutations may lead to HA and how the HA patient genotypes influence the risk of FⅧ inhibitor.     

Identification of a new peptide deformylase gene from enterococcus faecium and establishment of a new screening model targeted on PDF for novel antibiotics

Objective To identify a new peptide deformylase (PDF) gene (Genebank Accession AY238515) from Enterococcus faecium and to establish a new screening model targeted on PDE Methods A new PDF gene was identified by BLAST analysis and PCR and was subsequently over-expressed in the prokaryotic expression host E.coli B121(DE3). Over-expressed protein was purified for enzymatic assay by metal affinity chromatography and a new screening model was established for novel antibiotics. Result A new PDF gene of Enterococcus faecium was identified successfully. Ten positive samples were picked up from 8000 compound library and the microbial fermentation broth samples. Conclusion A new PDF of gene Enterococcusfaecium was first identified and the model had a high efficacy. Positive samples screened may be antibacterial agents of broad spectrum.     

Two novel STK11 mutations in three Chinese families with Peutz-Jeghers syndrome

Background Peutz-Jeghers syndrome (PJS) is an autosomal dominantly inherited disease. STK11/LKB1 gene germline mutations have been identified as responsible for PJS. In our study, we investigated the molecular basis of PJS and evaluated correlation between the STK11 mutations and the Chinese population.Methods We collected three pedigrees of PJS and screened the 9 exons and their flanking intronic sequences of STK11/LKB1 gene in the probands and normal individuals in the families using polymerase chain reaction (PCR) and direct sequencing.Results Sequencing of the STK11 gene in the probands of 3 families revealed two novel mutations (c180C→G and c998-1002delGCAGC) in exon 1 and exon 8, respectively. The mutation of c180C→G resulted in a premature termination codon. The other mutation, a deletion of five nucleotides (998-1002delGCAGC) in exon 8, predicted to generate a translational frameshift and a termination at codon 1070.Conclusions The growing number of mutations in PJS pedigrees suggests the molecular basis of PJS. STK11 gene mutation can be detected in most patients with PJS.     

Proteolipid protein 1 gene mutation in nine patients with Pelizaeus-Merzbacher disease

Background Pelizaeus-Merzbacher disease （PMD） is a rare X-linked recessive disorder with symptoms including nystagmus, impaired motor development, ataxia, and progressive spasticity. The proteolipidprotein 1 （PLP1） gene is the only pathogenic gene of PMD. Duplication of the PLP1 gene is the most frequent gene defect, accounting for 50%-70% of PMD cases, whereas point mutations in the coding sequence or the splice sites account for 10%-25% of PMD cases. This study aimed to identify PLP1 mutations in nine unrelated Chinese patients （P1-9） with PMD, and 14 subjects from the family of patient 2 were also described. Methods Genomic DNA was extracted from peripheral multiplex ligation-dependent probe amplification （MLPA）. AI amplified and analyzed using direct DNA sequencing. blood samples. Gene dosage was determined using the 7 exons and exon-intron boundaries of the PLP1 gene were Results Of these nine patients, there were four transitional, four classical, and one connatal PMD according to their clinical and radiological presentations. PLP1 duplications were identified in patients 1-7 with PMD. Their mothers were PLPI duplications carriers as well. Both duplication carriers and normal genotypes of PLP1 were identified in the family members of patient 2. A c.517C〉T （p. P173S） hemizygous missense mutation in exon 4 was found in patient 8 with PMD, and his mother was shown to be a heterozygote of this mutation. Conclusions We identified seven genomic duplications and one missense mutation （p. P173S） of the PLP1 gene in eight Chinese patients with PMD. This is the report about PLP1 mutations in PMD patients from the mainland of China.     

bcl 10 gene mutation in hepatocellular carcinoma

Objective To detect the mutation frequency of the bcl 10 gene in the early and advanced st ages of hepatocellular carcinoma (HCC).Methods Genome DNA samples were extracted from 46 cases of fresh HCC tumor tissues and t heir non-tumor adjacent tissues. Polymerase chain reaction-single strand conf ormation polymorphism method was used to detect point mutations of t he three exons of the bcl 10 gene. For each individual exon, six random samples from those showing abnormal DNA bands were sequenced to verify those mutations . The relationship between serum alpha-fetoprotein (AFP) level and bcl 10 muta tion, between the tumor size and bcl 10 mutation was also analyzed.Results Among the 46 samples, 26 cases (56.5%) were found to have mutations in exon 1, 5 out of the 6 cases were shown to have 5744 C→G mutation by sequencing; 25 cas es (54.3%) were found to have mutations in exon 2, 4 out of the 6 cases were sh own to have 11 311 T deletion mutation by sequencing. Twenty-one cases (4 5.7%) were found to have mutations in exon 3, all of the 6 cases selected for sequenc ing were shown to have 14 116 C→T mutation. Statistical analysis showed t hat ne ither serum alpha-fetoprotein level nor the size of hepatocellular carcino ma has a significant relationship with bcl 10 mutation.Conclusion The bcl 10 gene has a high mutation frequency in liver cancer.     

MISE AU POINT D＇UNE TECHNIQUE D＇ADMINISTRATION IN VIVO DES VECTEURS GENETIQUES DANS LE MUSCLE CARDIAQUE

Objective In order to improve the in vivo gene transfer into the heart muscle, we have de-signed α ECG-synchronized microinjection system that allows sequential gene delivery to the myocardium.Methods A cannula was introduced into the right carotid artery of the Wistar rat under general anesthesia. With the ECG-synchronized injection during diastole, the genetic vector (Ad CMV lacZ ) infusion was per-formed with various concentrations( 10^7-10^10pfu ) and different frequency ( the ratio of heart beats per injec-tion from 1 : 1 to 4 : 1 ). The hearts of the rats were removed after 7 days for histological examination. Results Best results were obtained with a total vector amount of 10^9 pfu and a good ratio 3 : 1 between heart frequency and injection frequency. The transfection efficiency was increased by use of vasodilators and by an increase of vascular permeability. No signs of myocardial ischemia or ventricular arrythmia were observed. Conclusion We have established a novel and safe method for in vivo gene transfer into the heart. Transgene expression suggests that this method may be useful technique to study cardiac function of treat cardiac diseases by means of gene therapy.     

风湿病人群硫唑嘌呤代谢酶基因型与药物耐受性的关系

目的 探讨风湿病患者硫嘌呤甲基转移酶（TPMT）基因型与硫唑嘌呤耐受性的关系。方法采用等位基因特异性的聚合酶链反应（AS-PCR）方法和聚合酶链反应-限制性片段长度多态性（PCR-RFLP）方法检测200例风湿病患者4种常见TPMT突变等位基因TPMT^＊2（G238C）、TPMT^＊3A（A719G／G460A）、TPMT^＊3B（G460A）和TPMT^＊3C（A719G）。194例患者使用了硫唑嘌呤（剂量50～150mg／d）,并随访观察3个月。结果在200例风湿病患者中检测到4例TPMT^＊3C杂合子,没有检测到TPMT^＊2、TPMT^＊3B、TPMT^＊3A型突变。基因型频率：野生型基因纯合子为98％,杂合子TPMT^＊1／TPMT^＊3C为2％。风湿病患者突变等位基因频率为1％。4例TPMT^＊3C杂合子TPMT活性平均值为（2．44±1．2）U／ml红细胞,196例野生型基因纯合子TPMT活性平均值为（12．24±6．8）U／ml红细胞。TPMT^＊3C杂合子的酶活性均值显著低于野生型基因纯合子,差异有统计学意义。194例使用硫唑嘌呤的患者中18例出现骨髓抑制,2例为严重造血系统危象,6例合并出现肝功能损害。4例TPMT^＊3C杂合子患者除1例未使用硫唑嘌呤外,其余3例均在用药后1个月内出现骨髓抑制,包括2例严重造血系统危象。结论存在TPMT突变等位基因的患者对硫唑嘌呤不耐受,可能发生严重造血系统危象。在用药前检测TPMT基因型对提高治疗的安全性有重要意义。     

汉族人群药物代谢酶基因多态性位点基因型分布频率的研究

目的 了解汉族人群7种主要药物代谢酶基因14个多态性位点基因型的分布频率及其特征.方法 收集1382名汉族人外周血样品,常规提取基因组DNA.用PCR-限制性内切酶片段长度多态性方法检测细胞色素P450酶(CYP450)的CYP3A4 * 1B、CYP3A5 * 3、苯醌氧化还原酶1(NQO1)的C609T(NQO1_(C609T))、髓过氧化物酶(MPO)的G463A(MPO_(G463A))、5,10-亚甲基四氢叶酸还原酶(MTHFR)的C677T(MTHFR_(C677T))、A1298C(MTHFR_(A1298C))、N-乙酰基转移酶2(NAT2)的NAT2* 5A_(C481T)、NAT2 * 6A_(G590A)、NAT2 * 7A_(G857A)和巯基嘌呤-S-甲基转移酶(TPMT)的TPMT * 3B_(G460A)、TPMT * 3C_(A719G)多态性位点基因型,用多重PCR方法检测谷胱甘肽硫转移酶(GST)的GSTM1、GSTT1基因型,用等位基因特异性PCR(AS-PCR)检测,TPMT * 2_(G238C)基因型.结果 野生、杂合变异和纯合变异基因型频率CYP3A4 * 1B分别为99.8%、0.2%和0,CYP3A5 * 3为8.4%、34.3%和57.3%;NQO1_(C609T)为28.7%、49.7%和21.6%;MPO_(G463)A为75.0%、23.2%和1.8%;MTHFR_(C677T)为25.9%、44.9%和29.2%,MTHFR_(A1298C)为67.3%、30.4%和2.3%;TPMT * 3C_(A719G)为96.8%、3.2%和0.表达型和缺失型基因型频率GSTM1分别为36.1%和63.9%,GSTT1分别为54.4%和45.6%.NAT2*4/*4、*4/*5、*4/*6、*4/*7、*5/*5、*5/*6、*5/*7、*6/*6、*6/*7和*7/*7基因型频率分别为34.5%、4.3%、24.3%、18.2%、0.1%、1.8%、1.5%、5.0%、7.6%和2.6%,NAT2*4、*5、*6和*7等位基因频率分别为57.9%、3.9%、21.8%和16.3%,快乙酰化和慢乙酰化基因表型频率分别为81.4%和18.6%.TPMT*2_(G238C)和TPMT*3B_(G460A)野生基因型频率均为100%.结论 药物代谢酶基因常见的遗传多态性在中国汉族人群中的分布及其频率与白种人和黑种人存在明显差异,与亚洲其他黄种人也存在一定的差异.     

巯嘌呤治疗儿童急性淋巴细胞白血病相关毒副作用及其与TPMT基因多态性关系的研究

目的:观察CCLG-08方案中含有巯嘌呤的巩固和维持阶段急性淋巴细胞白血病(Acute lymphoblastic leukemia,ALL)简称急淋。患儿毒副作用的发生情况,检测急淋患儿巯嘌呤甲基转移酶(Thiopurine S-methyltransferase,TPMT)基因多态性,研究其与巯嘌呤相关药物毒副作用的关系。方法:观察急淋患儿巩固和维持阶段发生的以外周血白细胞显著减少、肝脏损害为主的毒副作用;采用等位基因特异性聚合酶链反应、限制性片断长度多态性和时间飞行质谱技术检测TPMT基因G238C、G460A、A719G多态性。结果:急淋患儿巩固化疗阶段外周血白细胞显著减少的血液系统毒副作用发生率是19.35%(n=24);维持治疗1个月以上,外周血白细胞显著减少的血液系统毒副作用发生率是13.82%(n=13),肝脏损害的发生率是10.64%(n=10);维持治疗Ⅰ和Ⅱ组急淋患儿的血液系统毒副作用和肝损害发生率没有显著的统计学差异。没有发现急淋患儿TPMT基因型与其巯嘌呤相关毒副作用间的相关性。结论:研究显示急淋患儿可以良好耐受CCLG-08方案中的巩固和维持治疗;汉族急淋患儿TPMT基因G238C...     

MTHFR及TPMT基因多态性对儿童急性淋巴细胞白血病化疗不良反应的影响

目的 探讨亚甲基四氢叶酸还原酶(MTHFR)及巯嘌呤甲基转移酶(TPMT)单核苷酸基因多态性(SNP)对急性淋巴细胞白血病(ALL)儿童化疗后不良反应的影响.方法 选择2014年1月至2016年10月对该院儿内血液科收治的98例ALL患儿,采用梯度PCR及DNA测序技术,检测MTHFR C677T、A1298C及TPMT A719G、G460A的基因型,比较不同SNP与化疗后不良反应的关系.结果 ALL患儿MTHFRC677T和A1298C的突变率分别为66.33％和44.90％,TPMT A719G、G460A的突变率分别为12.24％及9.18％.MTHFR A1298AC发生血小板降低的比例(28.13％)高于A1298AA基因型(7.41％)与A1298CC基因型(8.33％),比较差异有统计学意义(P＜0.05).MTHFR A1298AA发生黏膜损伤的比例(9.26％)低于A1298AC基因型(43.75％)与A1298CC基因型(50.00％),比较差异有统计学意义(P＜0.05).MTHFRC677T、TPMT A719G、G460A等基因型与化疗后不良反应比较差异均无统计学意义(P＞0.05).结论 MTHFR A1298C与ALL患儿MTX化疗后不良反应的发生有关.     

应用等位基因特异性PCR检测胆固醇酯转运蛋白基因突变

目的:建立检测胆固醇酯转运蛋白(cholesterol ester transfer protein,CETP)基因6种常见突变的等位基因特异性PCR技术。方法:应用针对CETP基因TaqIB(G→A)、I405V(A→G)、D442G(A→G)、R451Q(G→A)、A373P(G→C)和I14A(G→A)这6种常见的突变位点设计的等位基因特异性PCR技术,对海南汉、黎族人群中CETP基因突变类型进行了检测,同时对经上述等位基因特异性PCR检测的样本进行序列测定。结果:在海南汉、黎族人群中,TaqIB(G→A)突变位点可检测出GG、GA、AA3种基因型,I405V(A→G)突变位点可检测出AA、AG、GG3种基因型,D442G(A→G)突变位点可检测出AA、AG2种基因型,但在海南汉、黎族人群中未检测到R451Q(G→A)、A373P(G→C)和I14A(G→A)3种突变类型,用等位基因特异性PCR鉴定的CETP基因突变的基因分型结果与序列测定结果完全符合。结论:等位基因特异性PCR技术操作简便,重复性和稳定性好,可作为鉴定CETP基因突变类型的可行方法。     

成人急性淋巴细胞白血病巯嘌呤甲基转移酶基因多态性研究

目的研究我国成人急性淋巴细胞白血病（ALL）患者及健康汉族人群巯嘌呤甲基转移酶（TPMT）基因多态性。方法从78例成人ALL患者和154例健康汉族人外周血提取白细胞基因组DNA,采用等位基因特异性PCR（AS-PCR）和PCR结合限制性片断长度多态性（PCR-RFLP）技术对TPMT＊2、TPMT＊3A、TPMT＊3B和TPMT＊3C的等位基因频率进行分析。结果在成人ALL患者和健康汉族人中仅检测到6例TPMT＊3C杂合子,没有检到TPMT＊2、TPMT＊3A和TPMT＊3B。成人ALL患者TPMT总的突变型等位基因频率（1．28％）与健康汉族人群（1．30％）相近。结论TPMT＊3C可能是中国成人ALL和健康汉族人群最主要的突变型等位基因,预先检测TPMT基因型对使用巯嘌呤类药物治疗的中国成人ALL患者有临床裨益。     

Altofrequency SNPs of mitochondrial DNA in 26 Han Chinese

Objective, To explore the possible mitochondrial DNA （mtDNA） polymorphism in Han Chinese. Methods： The complete mitochondrial genome of 26 unrelated healthy Han Chinese were extracted and sequenced. Results： The mtDNA nucleotide sites （2 706, 7 028, 8 860, 11 719, and 15 326） were found totally different from the Revised Cambridge Reference Sequence （rCRS）. These single nucleotide polymorphisms （SNPs） were 2 706 A→G, 7 028 C→T, 8 860 A→G, 11 719 G→A, 15 326 A→G. Conclusion, These findings provide new insights into the characteristics of Han Chinese mitochondrial genetic diversity.     

汉族炎症性肠病患者硫嘌呤甲基转移酶多态性与硫唑嘌呤药物毒副作用及疗效的相关性研究

研究目的：探讨汉族炎症性肠病（IBD）患者硫嘌呤甲基转移酶（TPMT）基因多态性及活性与硫唑嘌呤药物毒副作用及疗效的关系,从而提高用药安全性,建立个体化治疗方案。研究方法：对52例接受硫唑嘌呤(AZA)维持治疗的IBD患者监测骨髓抑制及肝脏毒性的发生情况,并运用引物特异性PCR及PCR-RFLP方法进行TPMT*2,*3A,*3B,*3C四种突变等位基因检测。进一步采用反相高效液相色谱法（HPLC）,对其中13例患者进行红细胞内TPMT活性检测,初步探讨汉族IBD患者TPMT基因多态性及活性与AZA药物毒副作用及疗效的关系。研究结果：在对52例接受AZA治疗的IBD患者的随访中,观察到有5例患者发生了骨髓抑制,1例发生了肝脏毒性。而基因多态性检测发现该6例患者均不存在TPMT*2,*3A,*3B,*3C这4种常见的TPMT突变等位基因。在TPMT 活性的研究中发现,发生早期骨髓抑制的3例患者TPMT平均活性低于没有发生骨髓抑制的患者（9.3±2.1 U/ml pRBC vs 18.0±6.2 U/ml pRBC;p=0.046）,并且低于早期未发生骨髓抑制的患者组（9.3±2.1 U/ml pRBC vs 17.7±5.5 U/ml pRBC;p=0.029）。发生肝脏毒性的患者1例,TPMT活性为28.8 U/ml pRBC,明显高于没有发生肝脏毒性的患者（14.7±4.8U/ml pRBC）。AZA治疗中维持缓解的IBD患者TPMT活性显著低于没有诱导缓解的患者（13.7±3.5 U/ml pRBC vs 22.0±5.5 U/ml pRBC;p=0.009）。结论： TPMT基因多态性检测并不能很好地解释AZA药物毒副作用;而初步研究发现TPMT活性能较好的预测早期药物毒副作用的发生及治疗疗效。     

20例中国Peutz-Jeghers综合征患者STK11基因编码区突变分析

目的检测Peutz-Jeghers综合征患者STK11基因编码区序列,进一步明确STK11基因可能存在新的突变位点。方法收集空军总医院2009年1月~2010年10月期间收治的20例Peutz-Jeghers综合征患者的血液样本,采用PCR扩增技术及DNA测序方法检测STK11基因编码区序列,与STK11基因的正常序列比对分析。结果 20例Peutz-Jeghers综合征患者中有14例患者检测到STK11基因的编码区发生突变,1例患者携带2个突变位点,13例患者携带单一突变位点。测序发现1例患者在3号外显子第460位发现一错义突变(460C→G),在第154密码子处形成另一种新的氨基酸,为一新的突变位点。2个家系中4例患者在同一位点发生突变;同一家系患者的突变位点一致。其余6例患者STK11基因编码区未见突变位点。结论 STK11基因突变是Peutz-Jeghers综合征发生的主要病因,3号外显子第460位错义突变,即460C→G,是导致Peutz-Jeghers综合征发生新的突变位点。     

一种新的G6PD基因突变型的鉴定

目的:鉴定1例葡萄糖-6-磷酸脱氢酶缺乏症患者的基因突变。方法:用聚合酶链反应、限制性内切酶筛查葡萄糖-6-磷酸酶基因1388G→A、1376G→T、1360C→T、1024C→T、592C→T、517T→C、493A→G,487G→A、392G→T、95A→G突变,用单链构象多态性筛查葡萄糖-6-磷酸脱氢酶基因的所有外显子,用核苷酸序列测定确定基因突变。结果:该患者未存在1388G→A、1376G→T、1360C→T、1024C→T、592C→T、517T→C、493A→G、487G→A、392G→T、95A→G突变,但在外显子8发现了一种新的G6PD基因突变———835A→G突变,此突变导致第279位的苏氨酸被丙氨酸取代,将其命名为G6PD-海口,其酶活性约是正常的10%,比835A→T突变型的活性低,后者的酶活性约是正常的40%;分析人G6PD的三维结构模型表明,第279位苏氨酸残基的羟基对于维持G6PD亚基的相互作用具有非常重要的作用。结论:835A→G突变是一种新的G6PD基因突变型,G6PD的第279位苏氨酸残基的羟基是维持G6PD亚基相互作用及酶活性的必需基团。