中国人圆锥角膜患者的TGFBI基因编码区点突变及多态性的检测和分析

Objective To investigate the point mutations and polymorphisms of transforming growth factor β-induced gene (TGFBI) in Chinese patients with keratoconus and discuss the relationship between the feature of gene mutations and single nucleotide polymorphisms of TGFBI gene and keratoconus. Methods Polymerase chain reaction-single strand conformation polymorphism and DNA direct sequencing were performed in 30 keratoconus cases and 30 healthy controls. All 17 exons of the TGFBI gene were analyzed for point mutations and single nucleotide polymorphisms. Results Totally two heterozygous nucleotide changes were identified in exon 12 of the TGFBI gene. The codon 535 is changed from GGA to TGA in 1 patient, leading to a substitution of glycine to a stop codon at the protein level (G535X). The codon 540 is changed from TTT to TTC in 2 patients and 1 control individual, resulting in a nonsense mutation (F54F),and is a single nucleotide polymorphism of the gene. Conclusion Mutation and polymorphisms of the TGFBI gene were detected in Chinese patients with keratoconus in this study. The results suggest that TGFBI gene might play an important role in the pathogenesis of keratoconus.     

中国人圆锥角膜患者的TGFBI基因编码区点突变及多态性的检测和分析

目的 检测中国人圆锥角膜患者TGFBI基因编码区点突变及单核苷酸多态性特点,探讨TGFBI基因与圆锥角膜的关系.方法 应用聚合酶链反应-单链构象多态性和DNA直接测序技术,对30例圆锥角膜患者、30名正常对照外周血TGFBI基因编码区的17个外显子,进行了点突变和单核苷酸多态性的检测和分析.结果 共发现2种TGFBI基因碱基变异,位于第12外显子,均为杂合性.1例圆锥角膜患者在TGFBI基因密码子535位点发生GGA→TGA置换,引起甘氨酸突变为终止密码(G535X),在对照组中未检出此突变;2例圆锥角膜患者和1名健康对照者在TGFBI基因密码子540位点发生TTT→TTC置换,不引起编码的苯丙氨酸改变(F540F),系TGFBI基因的多态性改变.结论 中国圆锥角膜人群存在着TGFBI基因变异,提示TGFBI基因在圆锥角膜的发病中可能起一定的作用.

Abstract：

Objective To investigate the point mutations and polymorphisms of transforming growth factor β-induced gene (TGFBI) in Chinese patients with keratoconus and discuss the relationship between the feature of gene mutations and single nucleotide polymorphisms of TGFBI gene and keratoconus. Methods Polymerase chain reaction-single strand conformation polymorphism and DNA direct sequencing were performed in 30 keratoconus cases and 30 healthy controls. All 17 exons of the TGFBI gene were analyzed for point mutations and single nucleotide polymorphisms. Results Totally two heterozygous nucleotide changes were identified in exon 12 of the TGFBI gene. The codon 535 is changed from GGA to TGA in 1 patient, leading to a substitution of glycine to a stop codon at the protein level (G535X). The codon 540 is changed from TTT to TTC in 2 patients and 1 control individual, resulting in a nonsense mutation (F54F),and is a single nucleotide polymorphism of the gene. Conclusion Mutation and polymorphisms of the TGFBI gene were detected in Chinese patients with keratoconus in this study. The results suggest that TGFBI gene might play an important role in the pathogenesis of keratoconus.     

Mutational screening of affected cardiac tissues and peripheral blood cells identified novel somatic mutations in GATA4 in patients with ventricular septal defect

The aim of this study was to examine how somatic mutations of the GATA4 gene contributed to the genesis of ventricular septal defect (VSD). The coding and intron-exon boundary regions of GATA4 were sequenced of DNA samples from peripheral blood cells and cardiac tissues of twenty surgically treated probands with VSD. Seven novel heterozygous variants were detected in cardiac tissues from VSD patients, but they were not detected in the peripheral blood cells of VSD patients or in 500 healthy control samples. We replicated 14 single nucleotide polymorphisms (SNPs) reported in NCBI. Bioinformatics analysis was performed to analyze the possible mechanism by which mutations were linked to VSD. Among those variants, c. 1004C>A (p.S335X) occurred in the highly conserved domain of GATA4 and generated a termination codon, which led to the production of truncated GATA4. The seven novel heterozygous GATA4 mutations were only identified in cardiac tissues with VSD, suggesting that they are of somatic origin. A higher mutation rate in cardiac tissues than in peripheral blood cells implies that the genetic contribution to VSD may have been underestimated.     

中国Rett综合征患儿突变基因的亲源分析

Objective To identify the parental origin of methyl-CpG-binding protein 2 (MECP2)gene mutations in Chinese patients with Rett syndrome. Methods Single nucleotide polymorphisms (SNPs) in intron 3 of the MECP2 gene were analyzed by PCR and sequencing in 115 patients with Rett syndrome.Then sequencing of the SNP region was performed for the fathers of the patients who had at least one SNP,to determine which allele was from the father. Then allele-specific PCR was performed and the products were sequenced to see whether the allele from father or mother harbored the mutation. Results Seventy-six of the 115 patients had at least one SNP. Three hot SNPs were found in these patients. They were: IVS3+22C＞G, IVS3+266C＞T and IVS3+683C＞T. Among the 76 cases, 73 had a paternal origin of MECP2 mutations, and the other 3 had a maternal origin. There were multiple types of MECP2 mutation of the paternal origin, including 4 frame shift, 2 deletion and 67 point (56 C＞T, 6 C＞G, 2 A＞G, 2 G＞T and 1 A＞T) mutations. The mutation types of the 3 ptients with maternal origin included 2 frame shift and 1 point (C＞T) mutation. Conclusion In Chinese RTT patients, the MECP2 mutations are mostly of paternal origin.     

中国Rett综合征患儿突变基因的亲源分析

Objective To identify the parental origin of methyl-CpG-binding protein 2 (MECP2)gene mutations in Chinese patients with Rett syndrome. Methods Single nucleotide polymorphisms (SNPs) in intron 3 of the MECP2 gene were analyzed by PCR and sequencing in 115 patients with Rett syndrome.Then sequencing of the SNP region was performed for the fathers of the patients who had at least one SNP,to determine which allele was from the father. Then allele-specific PCR was performed and the products were sequenced to see whether the allele from father or mother harbored the mutation. Results Seventy-six of the 115 patients had at least one SNP. Three hot SNPs were found in these patients. They were: IVS3+22C＞G, IVS3+266C＞T and IVS3+683C＞T. Among the 76 cases, 73 had a paternal origin of MECP2 mutations, and the other 3 had a maternal origin. There were multiple types of MECP2 mutation of the paternal origin, including 4 frame shift, 2 deletion and 67 point (56 C＞T, 6 C＞G, 2 A＞G, 2 G＞T and 1 A＞T) mutations. The mutation types of the 3 ptients with maternal origin included 2 frame shift and 1 point (C＞T) mutation. Conclusion In Chinese RTT patients, the MECP2 mutations are mostly of paternal origin.     

Relationship between nerve injury-induced protein gene 2 polymorphism and stroke in Chinese Han population

The aim of present study was to investigate the relationship between nerve injury-induced protein 2 (NINJ2) gene polymorphism and stroke in Chinese Han population.Fifty-two patients with large-artery atherosclerosis (LAA) infarction,85 patients with small-artery occlusion lacunar (SAO) infarction,50 patients with intracerebral hemorrhage (ICH) and 66 controls were included.Genotypes and alleles frequencies of the two single nucleotide polymorphisms (SNPs) of NINJ2 among different groups were analyzed and compared.In regard to rs12425791,the frequencies of the AG and AA+AG genotypes of the LAA and SAO groups were significantly higher than those in the control group;the frequency of the A allele of the SAO group was significantly higher than that of the control group.In regard to rs11833579,there were not any significant differences between the case and the control groups.The SNP rs12425791 is significantly associated with ischemic stroke,and the A allele increases the susceptibility to stroke.The SNP rs11833579 is not significantly associated with stroke.     

妊娠期糖耐量受损与Ghrelin基因多态性的关联性研究

Objective To investigate whether the polymorphism of the Ghrelin gene is associated with gestational impaired glucose tolerance and its distribution in Chinese Han population. Methods We assessed common genetic variation of the Ghrelin ten single nucleotide polymorphisms(SNP)in 94 patients with gestational impaired glucose tolerance and 102 control by using the restriction fragment length polymorphism method.. In addition, haplotype assays were conducted. Results The genotype distributions of these ten common polymorphisms in gestational impaired glucose tolerance patients were not significantly different from those of normal controls in statistics(x2=2.790,0.224,0.072,2.887,0.004,1.073,0.653,0.671;x2 =2.553,0.391,0. 108,4. 812,0. 005,3. 278,1. 308,3. 364, P ＞ 0. 05), but three haplotypes(SNP-1500G - SNP-1062G -SNP-994C - SNP-604G;SNP + 408C - SNP + 2488G - SNP + 3056C;SNP + 408A - SNP + 2488G - SNP +3056C)of the Ghrelin gene were found to be significantly associated with it in statistics(x2 =4.336,4.308,5.327, P ＜0. 05). Conclusion The above mentioned ten common polymorphisms in the Ghrelin gene were not found to be significantly associated with susceptibility to gestational impaired glucose tolerance. However,one(SNP + 408C - SNP + 2488G - SNP + 3056C)of the Ghrelin haplotypes showed a protective role in gestational impaired glucose tolerance, and two(SNP-1500G- SNP-1062G - SNp-994C - SNP-604G ;SNP + 408A -SNP + 2488G - SNP + 3056C)showed higher susceptibility.     

Analysis of TGFBI gene mutation in a Chinese family with atypical Reis-Bückler corneal dystrophy

Objective To identify the TGFBI gene mutation and the relationship between genotype and phenotype of a Chinese family with atypical Reis-Bückler corneal dystrophy (RBCD). Methods Four patients, two non-carrier relatives of the family were enrolled in the present study. In addition to ophthalmologic examinations, PCR amplification and DNA sequencing of exons 4, 11, 12, and 14 of the TGFBI gene were carried out. Exon 14 was also sequenced in 100 healthy controls. Results A G to A transition at eodon 623 in all affected members was identified. This mutation resulted in a substitution of glyeine (GGC) to aspartic acid (GAC) at the protein level. None of the healthy family members, or any of the 100 control subjects carried this mutation. Conclusion The G623D mutation of the TGFBI gene caused an atypical Reis-Buckler corneal dystrophy in this family. This mutation is reported in Chinese for the first time.     

Level of functioning of siblings and parents of probands of varying degrees of retardation

A further analysis of already published data supports the position that retardates of low ability level less frequently have retarded siblings, retarded parents, and parents low in occupational level than do retardates higher in ability level. The analysis supports the position that there are two types of retarded individuals, persons retarded as a result of gene or chromosomal anomalies, brain injury, etc., who more frequently occur in the lower-level retardate group, and persons whose retardation represents polygenic segregation, who more frequently occur in the higher-level group.     

Modes of Inheritance of Errors of Refraction

Eighteen families in which both parents had refractions within the range of +4·0 D to −4·0 D and axial lengths seen in emmetropia (22·3-26·0 mm) showed coefficients of correlation of the order 0·5 indicative of polygenic inheritance. Such coefficients were seen for axial length (0·407) and for the cornea (0·487), but not for the lens (which is known to be yoked to the axial length). No such coefficients were seen in 19 families in which one of the parents had axial length outside the emmetropic range (nine families with long axes and 10 with short axes).

The pattern of polygenic inheritance for emmetropia (completely correlated optical components) and errors of refraction up to 4·0 D (inadequately correlated components: correlation ametropia) follows that seen in stature and other measurable characters. In contrast the high refractive errors with their abnormal axial lengths (component ametropia) are—like the extremes in stature—pathological anomalies with monofactorial inheritance.

     

Aspects of the problem of direct introduction of Standards of International Organizations

Editorial note. This article is published as part of a discussion. Particular issues of the article are disputable. First of all, this concerns the so-called “folder” method of introduction of international standards for medical devices to domestic medical practice (i.e., by direct translation of the standards and their publication as standardizing documents). Nevertheless, at least one of the problems, the problem of coordination between domestic state standards for medical devices and international recommendations of ISO and IEC, is undoubtedly of topical importance. Advancement of new health service legislation which is to be approved by law-makers will definitely introduce corrections into the present situation. The Editorial Board of Meditsinskaya Tekhnika believes this article will lessen these problems and to be welcomed by readers.