Prenatal diagnosis of de novo mosaic deletion 13q associated with multiple abnormalities.

A case of prenatal diagnosis of de novo mosaic deletion of the long arm of chromosome 13 (del(13)(q13.3)) is presented. Routine scanning in a 27-year-old primigravida at 25 weeks' gestation showed fetal bilateral hydronephrosis. Detailed anomaly scanning in our tertiary referral center further demonstrated posterior meningoencephalocele, sloping forehead, microcephaly, syndactyly and hypoplastic thumbs. Both genetic amniocentesis and cordocentesis revealed a mosaic karyotype, 46,XY/46,XY,del(13)(q13.3). Sonographic findings were confirmed by postmortem autopsy and additional abnormalities such as agenesis of corpus callosum, hypoplastic cerebellum and macroglossia were diagnosed. Detailed sonography in this case thus revealed multiple malformations that prompted fetal karyotyping at 25 weeks' gestation.     

Genetic basis of tobacco smoking: strong association of a specific major histocompatibility complex haplotype on chromosome 6 with smoking behavior

The genetic basis for addiction to tobacco smoking--particularly that of the perception of olfactory stimuli that may be important in reinforcing smoking addiction--is largely unknown. A cluster of genes for olfactory receptors is in close proximity to the MHC region on chromosome 6. Polymorphisms of MHC class III genes (RCCX modules, TNFA promoter polymorphisms) were determined in 101 healthy subjects and 232 coronary artery disease (CAD) patients from Hungary with defined tobacco smoking habits. A highly significant association between ever smoking (past + current smokers) and a specific MHC haplotype was observed (odds ratios = 2.14-4.13; P-values = 0.012 to <0.001). This haplotype is characterized by the presence of C4A null alleles and a solitary short C4B gene linked to the TNF2 allele of the promoter for TNFA gene. This haplotype occurred more frequently in the ever smokers than in the never smokers [odds ratio: 4.97 (1.96-12.62); P = 0.001], and such associations were stronger in women (odds ratio = 13.6) than in men (odds ratio = 2.79). An independent study of complement C4 protein polymorphism and smoking habits in Icelandic subjects (n = 351) yielded similar and confirmative results. Considering the documented link between olfactory stimuli and smoking in females, and the presence of a cluster of odorant receptor genes close to the MHC class I region, our findings implicate a potential role of the MHC-linked olfactory receptor genes in the initiation of smoking.     

The elastin gene is disrupted in a family with a balanced translocation t(7;16)(q11.23;q13) associated with a variable expression of the Williams-Beuren syndrome

The Williams-Beuren syndrome (WBS) is a complex developmental disorder with multisystemic manifestations including supravalvular aortic stenosis (SVAS), a so-called elfin face, a hoarse voice, and a specific cognitive phenotype. Most WBS patients have a >1 Mb deletion on one of their chromosomes 7 in q11 but except for elastin, whose haploinsufficiency causes the cardiovascular malformations, it is unknown which genes in the deletion area contribute to the phenotype. We have investigated a family with a cytogenetically balanced translocation t(7;16)(q11.23;q13) in which affected individuals manifested a broad spectrum of clinical phenotypes ranging from a hoarse voice as the only feature to the full WBS phenotype. Molecular cytogenetic and DNA sequence analyses of the translocation breakpoint showed that the cytogenetic rearrangement disrupts the elastin gene locus within intron 5 in the exact same manner in all translocation carriers. The recently described large inversion of the 7q11.23 region was not present in this family. Our data demonstrate that disruption of the elastin gene by a translocation breakpoint may cause classical WBS, atypical WBS, SVAS, or no recognisable phenotype, and provide a clear example for extensive phenotypic variability associated with a position effect in humans.     

Anti-cholesterol antibodies (ACHA) in patients with different atherosclerotic vascular diseases and healthy individuals. Characterization of human ACHA

In animal experiments the protective role of anti-cholesterol antibodies (ACHA) in the development of atherosclerosis has been demonstrated. Despite the fact that ACHA are present in the serum of healthy humans, no data on the occurrence of these antibodies in human diseases are available. We determined serum concentrations of IgG type ACHA by an enzyme immunosorbent assay in 600 patients with atherosclerotic vascular diseases (86 patients with peripheral occlusive atherosclerosis, 146 patients with cerebrovascular diseases, 341 patients with severe coronary heart disease (CHD) who received aorto-coronary by-pass, 27 patients with myocardial infarction who did not undergo by-pass operation), in 57 patient controls (complaints of CHD, without coronarographic alterations) and in 218 healthy individuals. ACHA were present in the sera of all persons tested. No serum cofactor is needed for the binding of human ACHA to solid phase cholesterol, binding can be inhibited dose-dependently by LDL and even more strongly with LDL/VLDL preparations purified from human serum. ACHA levels were found to be considerably lower in patients with peripheral occlusive atherosclerosis and cerebrovascular diseases compared with the levels in healthy individuals. By contrast, the ACHA levels of patients with CHD were considerably higher. No differences in the IgG subclass distribution and binding efficiency of ACHA in the sera of CHD patients and controls were found. Thus, our present findings indicate that both low and high ACHA production may be associated with different atherosclerotic vascular diseases.     

Involvement of polymorphisms in the chemokine system in the susceptibility for coronary artery disease (CAD). Coincidence of elevated Lp(a) and MCP-1 -2518 G/G genotype in CAD patients

Genetic variation in the hepatic lipase (HL) gene (LIPC) promoter is an important determinant of HL activity in Caucasians. As HL activity is increased in patients with type 2 diabetes mellitus, we have investigated whether the -514 C-to-T polymorphism acted independently of type 2 diabetes to regulate HL activity. The frequency of this polymorphism and its effect on plasma HL activity and lipids were examined in 203 Chinese patients with type 2 diabetes and 205 controls. The frequency of the T allele was 0.343 and 0.376 in male and female diabetic patients, respectively, compared with 0.371 and 0.372 in male and female controls. The effect of LIPC genotype on HL activity was similar between men and women, and between diabetic patients and non-diabetic controls, with the lowest HL activity being found in those subjects with the TT genotype. On multivariate analysis, gender, LIPC genotype, the presence of type 2 diabetes and body mass index were independent predictors of HL activity, accounting for 22, 9, 5 and 3%, respectively, of the variance in HL activity (whole model adjusted R(2)=0.39, P<0.0001). The T allele was associated with higher high-density lipoprotein in the controls but not in the diabetic patients, and no associations were found between LIPC genotype and low-density lipoprotein subfractions in either groups. In conclusion, despite the higher frequency of the T allele in Chinese than in Caucasians, gender was the best predictor for HL activity, with LIPC gene polymorphism and type 2 diabetes making relatively smaller contributions to the variation in HL activity.     

Singleton exome sequencing of 90 fetuses with ultrasound anomalies revealing novel disease-causing variants and genotype–phenotype correlations

Exome sequencing has been increasingly implemented in prenatal genetic testing for fetuses with morphological abnormalities but normal rapid aneuploidy detection and microarray analysis. We present a retrospective study of 90 fetuses with different abnormal ultrasound findings, in which we employed the singleton exome sequencing (sES; 75 fetuses) or to a lesser extent (15 fetuses) a multigene panel analysis of 6713 genes as a primary tool for the detection of monogenic diseases. The detection rate of pathogenic or likely pathogenic variants in this study was 34.4%. The highest diagnostic rate of 56% was in fetuses with multiple anomalies, followed by cases with skeletal or renal abnormalities (diagnostic rate of 50%, respectively). We report 20 novel disease-causing variants in different known disease-associated genes and new genotype–phenotype associations for the genes KMT2D, MN1, CDK10, and EXOC3L2. Based on our data, we postulate that sES of fetal index cases with a concurrent sampling of parental probes for targeted testing of the origin of detected fetal variants could be a suitable tool to obtain reliable and rapid prenatal results, particularly in situations where a trio analysis is not possible.Subject terms: Genetics research, Disease genetics     

NT-proBNP对急性心肌梗死患者新发房颤的预测价值研究

目的探讨N末端B型脑利钠肽前体(NT-proBNP)对急性心肌梗死患者新发房颤的预测价值。方法从2008年1月至2010年12月收住我院心脏监护室的患者中入选急性心肌梗死(AMI)患者293例,按照患者住院期间是否出现房颤(AF)分为房颤组(n=43)和非房颤组(n=250)。比较两组间差异,分析血浆NT-proBNP水平对新发房颤的预测价值。结果 (1)AMI患者住院期间出现新发房颤的比例为14.7%;(2)房颤组患者NT-proBNP水平明显高于非房颤患者,且平均年龄较大,左心室射血分数、血红蛋白含量和肾小球滤过率(eGFR)均低于非房颤组;(3)多因素Logistic回归分析显示NT-proBNP可独立预测急性心肌梗死患者新发房颤(OR4.918,95%CI1.662-14.549,P=0.004)。结论血浆NT-proBNP水平可独立预测急性心肌梗死患者新发房颤的发生,可用于患者危险分层及指导早期预防治疗。     

Treatment of patients with advanced chronic myelogenous leukemia with interferon-alpha-2b and continuous oral cytarabine ocfosfate (YNK01): a pilot study

The efficacy of continuous oral cytarabine ocfosfate (YNK01) (300 mg/day) in combination with interferon alpha (IFNalpha, 5x10(6) IU/day) was evaluated in patients with advanced chronic myelogenous leukemia, who previously failed to respond to IFNalpha-based therapies. Dose escalations up to 900 mg YNK01 were allowed in patients who failed to respond. In view of our results, four patients developed a complete hematological response after YNK01 was started. Among those who initially responded to YNK01, one complete cytogenetic response was achieved 18 months later. Although the data are preliminary, this is the first study showing that continuous administration of YNK01 along with IFNalpha is effective in patients with advanced chronic myelogenous leukemia.