STUDIES OF HLA-D REGION DNA POLYMORPHISM IN INSULIN-DEPENDENT DIBETES MELLITUS

Restriction fragment length polymorphisms (RFLPs) of peripheral leucocyte DNA in insulin-dependent diabetes mellitus (IDDM) patients and in controls were studied with Southern blot analysis. IDDM has been reportedly associated positively with the HLA-DR3 and-DR4 in Caucasians, with the HLA-DR3 and-DR9 in Chinese, and negatively with the HLA-DR2 in both Caucasians and Chinese, Using an HLA-DQβcDNA probe, an EcoRI 2.2 kb fragment is found associated with DR2 controls (r = 0.78, P=1×10~(-6)), but not with DR2 IDDM patients, their respective frequencies being significantly different (P=0.02). The authors also report here their new findings that the frequencies of the EcoRI3.0 kb and BamHI3.3 kb fragments are both decreased in the patient group (P=0.0032 and P=0.0018 respectively). This suggested certain kinds of mutation such as partial deletion or others in the IDDM patients might have caused the RFLP pattern change as compared to the normal DNA. RFLPs may provide valuable information in searching for the genetic basis of IDDM.     

Analysis of the degree of precision of a computer-assisted dietary survey method

A computer-assisted method for the registration of food intakes in real time according to a concise and simple procedure was subjected to a series of controls in order to assess precision. The method employs the 'portion' of a composite dish as unit of measure. The constancy of the portion was tested. The results show that the recipes of the diet of a subject may be stored and utilized in deferred time without loss of precision: data to be recorded in real time are then very limited. The length of period of analysis was also studied. The time of investigation should not be shorter than two weeks to obtain precise information on the feeding habits of an individual subject, whereas for a group of subjects the diary of a single day provides information of sufficient precision.     

Antigen Presentation By Class I Major Histocompatibility Complex Molecules: A Context for Thinking About HLA-G

PROBLEM: There is substantial data that support the efficacy of paternal leukocyte immunization (PLI) for the treatment of alloimmune mediated miscarriage; however, there is confusion regarding the laboratory test that should be performed to determine levels of maternal anti-paternal leukocyte antibodies (MAPLA). METHOD: Popular methodologies employed include: 1) microcytotoxicity (MCX), 2) mixed lymphocyte culture (MLC), and 3) cell flow cytometry crossmatch (FCXM). Cell flow cytometry crossmatch correlates well with the more difficult MLC assay although the former proves the more sensitive study. This work compares the MCX assays with FCXM. The study group consisted of ten women who had a history of three or more spontaneous abortions (SABs). All ten had very low levels (<10%) of MAPLA as measured by FCXM. Following PLI all subjects demonstrated elevated levels (>50%) of MAPLA by FCXM. At 12 weeks gestation, sera were simultaneously measured for MAPLA by MCX and FCXM. RESULTS: Although all ten patients had very high levels of MAPLA by FCXM during pregnancy, five of ten had antibodies to HLA Class I and two of ten had antibodies to HLA Class II paternal antigens by MCX. Furthermore, all patients who were positive by MCX to paternal Class I antigens were also positive to Class I antigens not seen in either parent. Both patients who were positive by MCX to paternal Class II antigens were also positive to maternal Class II antigens. Notable is that all ten women eventually delivered healthy infants. CONCLUSION: Based on this preliminary study, the MCX assay is neither sensitive or reliable enough to determine the need and/or to monitor the effectiveness of PLI. Flow cytometry should be the modality of choice when determining the need for alloimmunotherapy and to monitor the effectiveness of treatment.     

RENIN GENE POLYMORPHISM ASSOCIATED WITH ALDOSTERONE RESPONSIVENESS TO THE RENINANGIOTENSIN SYSTEM IN PATIENTS WITH ALDOSTERONE-PRODUCING ADENOMAS

1. Aldosterone levels in patients with unilateral aldosterone-producing adenomas may be responsive or unresponsive to the renin-angiotensin system, with the former often previously misdiagnosed as bilateral adrenal hyperplasia. 2. In tumours from patients in the responsive subgroup, renin mRNA is expressed in greater amounts than in tumours from patients in the unresponsive subgroup, or in normal adrenals. 3. We compared the frequency of four renin gene polymorphisms in peripheral blood DNA from the two subgroups and found significant associations between BglI, TaqI and HinfI restriction fragment length polymorphisms (RFLP) and aldosterone responsiveness. 4. Allelic variation in the constitutive renin gene was associated with a specific cause of hypertension.     

中国汉族群体D4S111位点的遗传多态性研究

目的：研究中国汉族群体中α艾杜糖苷酶基因Ｄ４Ｓ１１１位点的遗传多态性。方法：采用扩增片段长度多态性（ＡｍｐＦＬＰ）分析技术，检测了广州地区汉族无血缘关系健康个体９７名。结果：Ｄ４Ｓ１１１位点，在９７名无关个体中发现５个等位基因和９种基因型，等位基因片段长度为８３０～５１０ｂｐ，基因频率为０００５２～０３６０８，ＰＩＣ为０５９６６，杂合性为０７８。结论：中国汉族群体中Ｄ４Ｓ１１１位点具有高度多态性，并与其它种族间存在差异性。     

根除幽门螺杆菌疗效与细胞色素氧化酶P450 2C19基因多态性的关系

目的 比较雷贝拉唑与奥美拉唑三联疗法根除幽门螺杆菌（Hp）的疗效与细胞色素氧化酶P4502 C19（CYP 2C19）基因多态性的关系。方法 采用随机、对照研究方法，将169例因消化不良症状接受常规胃镜检查确诊为慢性胃炎且Hp阳性的连续患者分人两组：雷贝拉唑三联疗法组（RAC组85例）和奥美拉唑三联疗法组（OAC组84例）。Hp诊断依靠组织病理学检查并参考快速尿素酶试验、血清Hp抗体检测结果。RAC组、OAC组均给予三联治疗：RAC组：雷贝拉唑10mg，OAC组：奥美拉唑20mg，两组均联用羟氨苄青霉素1000mg和克拉霉素500mg，全部药物每日2次，疗程7d。采用聚合酶链式反应结合限制性内切酶技术（PCR-RFLP），进行CYP 2C19基因型分析，治疗结束后第28天用^14C尿素呼气实验检测Hp根除疗效。结果 160例完成治疗方案，RAC组及OAC组的Hp根除率按PP分析及ITT分析均无统计学差异（P〉0．05）。根据CYP 2C19基因型分析，160例中，弱代谢型（PM）、中间代谢型（IM）及强代谢型（EM）的Hp根除率分别为95．5%（21／22）、85．9％（73／85）和67．9％（36／53）。PM型及IM型的Hp根除率均显著高于EM型（P〈0．05），而PM型与IM型间差异无统计学意义（P〉0．05）。RAC组中，各基因型的Hp根除率差异无统计学意义（P〉0．05）。OAC组中。IM型与EM型间（P〈0．01）及EM型与PM型间（P〈0．05）差异均有统计学意义。结论 雷贝拉唑与奥美拉唑两种三联疗法均能有效根除Hp。总疗效差异无统计学意义。雷贝拉唑三联疗法疗效较稳定，个体间差异小。PM型及IM型的Hp根除率均较EM型为高。     

Schizophrenia susceptibility genes on chromosome 13q32

Schizophrenia is a complex mental disorder affecting approximately 1% of the general population worldwide.1 It has a high incidence in the general population, a poor prognosis and a poor outcome, in that it has become a major social problem. Family, twin, and adoption studies have clearly shown that a genetic component is quite likely to play an important role in determining susceptibility to schizophrenia. The genome-wide scan indicates that several chromosomal regions are linked to schizophrenia, some of which have been replicated independently including 6p21-24, 8p21-22, 13q14-33 and 22q11-12.2,3 This study was designed to detect two single nucleotide polymorphisms (SNPs) located in the 13q14-33 region, rs188608 at the STK24 locus and rs2892679 at the GPC6 locus, among Chinese population.