Identification of mutations in PKD1 and PKD2 genes in two Chinese families with autosomal dominant polycystic kidney disease / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify the responsible mutation of autosomal dominant polycystic kidney disease (ADPKD) in two Chinese families.</p><p><b>METHODS</b>Total genomic DNA of all available family members and 100 unrelated healthy controls was extracted from peripheral blood leukocytes using a standard phenol-chloroform procedure. All exons with intronic flanking sequences of the PKD1 and PKD2 genes in the probands were amplified by PCR. Mutations were detected directly by DNA sequencing. To evaluate the pathogenicity of the variations, family and control based analyses were performed.</p><p><b>RESULTS</b>Five sequence variants were identified in the two families including PKD1 :c.2469G to A, PKD1:c.5014_5015delAG, PKD1:c.10529 C to T, PKD2:c.568G to A and PKD2:c.2020 1_2020delAG. Among them, PKD1:c.2469G to A and PKD2:c.2020 1_2020 delAG were novel mutations. Furthermore, the frameshift and splicing site mutations detected in the affected individuals were not detected in their unaffected relatives and 100 unrelated normal controls.</p><p><b>CONCLUSION</b>PKD1:c.5014_5015delAG and PKD2:c.2020 1_2020delAG are the responsible mutations of family A and B, respectively, and PKD2:c.2020 1_2020delAG is a de novo mutation.</p>

Y chromosome variations and male infertility / 中华医学遗传学杂志

Male infertility is a common complex disease. Y-linked spermatogenic failure is an important cause for this disorder. Due to the presence of many repeat sequences and the frequent occurrence of non-allelic homologous recombination between the sequences in the male-specific region of the Y (MSY) region of the chromosome, Y chromosome possesses high variation rate. The variations may result in the dosage changes of spermatogenesis-related gene families and lead to male infertility. The present article reviews the recent progress of the study on Y chromosome variations, and its possible effect on spermatogenic function, in DNA level.

Recent advances in studies on autosomal dominant adult polycystic kidney disease / 中华医学遗传学杂志

Adult polycystic kidney disease (APKD) is a severe autosomal dominant inheritable renal disease with high incidence. Because of the late-onset of the disease, patients might have transferred the disease gene to the next generation when diagnosis is made. Since its pathogenic molecular mechanism is still not completely clear and the shortage of effective medicines, the prevention and treatment of the disease is still not satisfactory. In the present article, the recent advances in the research on the pathogenesis, gene diagnosis and management of APKD are reviewed.

Study on the distribution of Y chromosome haplogroups in Sichuan Han population / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the distribution characteristics of Y chromosome haplogroups in Sichuan Han population.</p><p><b>METHODS</b>Using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP), denatured high performance liquid chromatography (DHPLC) and DNA sequencing methods, 18 Y-chromosome bialletic markers were detected to type Y chromosome haplogroups in 341 unselected men from Sichuan Han population.</p><p><b>RESULTS</b>A total of 14 haplogroups were observed, in which haplogroups H2 and H4 were identified for the first time in Sichuan population, and haplogroups H14 and N* were found firstly in Chinese. There was a significant frequency difference of Y haplogroups between Sichuan Han population and Southern Han population.</p><p><b>CONCLUSION</b>More comprehensive frequency distribution data of Y chromosome haplogroups are obtained in Sichuan Han population, which would be helpful for understanding the association of Y chromosome background and the susceptibility to male specific diseases such as spermatogenic failure, prostate cancer, testical cancer and so on in present population.</p>

DAZ1/DAZ2 cluster deletion mediated by gr/gr recombination per se may not be sufficient for spermatogenesis impairment: a study of Chinese normozoospermic men / 亚洲男科学杂志(英文版)

<p><b>AIM</b>To explore the possible effect of the deleted in azoospermia (DAZ) copy cluster deletion on spermatogenesis in the Chinese population, the deletion of the azoospermia factor c (AZFc) region was analyzed in 346 normozoospermic men.</p><p><b>METHODS</b>Three DAZ single nucleotide variant loci and seven AZFc-specific sequence-tagged sites were examined with polymerase chain reaction (PCR)-restriction fragment length polymorphism and routine PCR.</p><p><b>RESULTS</b>Five (1.4%) of the normozoospermic men were found to have deletion of gr/gr-DAZ1/DAZ2. None of the men were found to have b2/b4-entire DAZ deletion.</p><p><b>CONCLUSION</b>The presence of gr/gr-DAZ1/DAZ2 deletion in five men with normozoospermia suggests that this deletion per se may not be sufficient for spermatogenic impairment in Chinese men.</p>

Important genetic etiology of infertile Chinese males: chromosome abnormality and deletion of DAZ gene copy in the AZFc region of Y chromosome / 中华男科学杂志

<p><b>OBJECTIVE</b>To investigate the correlation of male infertility with abnormality of chromosomal quantity and construction and with the deletion of DAZ gene copy in the AZFc region of Y chromosome.</p><p><b>METHODS</b>Included in the study were 247 azoospermic and 206 severe oligozoospermic patients, as well as 210 fertile men as controls. Multi-PCR and PCR-RFLP were used to analyze the deletion of DAZ gene copies in the AZFc region of Y chromosome. Chromosomal quantity and construction were detected by G-band in the 453 patients.</p><p><b>RESULTS</b>In the azoospermic and severe oligozoospermic patients, the incidences of chromosomal abnormality were 12.6% and 8.3%; the rates of complete DAZ deletion were 7.7% and 11.2%, and the rates of DAZ1/DAZ2 deletion were 7.3% and 4.9% respectively, but no deletion was detected in the controls.</p><p><b>CONCLUSION</b>There is a high frequency of chromosomal abnormality and DAZ gene copy deletion in patients with azoospermia and oligospermia, which suggests that chromosomal abnormality and partial and complete deletion of DAZ gene copy might be important genetic causes of Chinese male infertility.</p>

Possible association between 278C/A single nucleotide polymorphism of FKBP6 and idiopathic azoospermia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate 2 polymorphism sites in exon 3 and intron 2 of FKBP6 in Chinese population, while screening the gene mutations and polymorphisms in exons 3, 4 of FKBP6, and the association of these polymorphisms with azoospermia.</p><p><b>METHODS</b>Possible variations of exons 3, 4 and genotypes and frequencies of 2 polymorphic loci were examined by denaturing high-performance liquid chromatography(DHPLC) and PCR-restriction fragment length polymorphism(PCR-RFLP) technique in 177 azoospermia patients and 231 control individuals.</p><p><b>RESULTS</b>The observed allele frequencies conformed well to Hardy-Weinberg equilibrium. The frequency of 278A allele was significantly higher in controls than that in patients (P<0.05). C/T(s7797242) polymorphism was not found in either group and variations in exons 3, 4 were not detected.</p><p><b>CONCLUSION</b>278A polymorphism of FKBP6 gene was associated with idiopathic azoospermia, while C/T, 370G/A, 430G/C, 467T/C, 468G/A polymorphisms might be very rare in Chinese population.</p>

Screening for ZNF230 gene mutation and analysis of its correlation with azoospermia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the possible association between ZNF230 gene and azoospermia.</p><p><b>METHODS</b>Screening for mutation of all 6 exons of ZNF230 gene was performed by denaturing high performance liquid chromatography(DHPLC) in 99 patients with azoospermia and in 115 healthy men as controls.</p><p><b>RESULTS</b>An A-->G transition at nucleotide 316 in exon 6 was identified. There were significant differences in the distribution profiles of both allele and genotype frequencies between patient group and control group (P < 0.01 and P < 0.05, respectively). In addition,there was a statistically significant difference in the serum follicle stimulating hormone (FSH) level between the patients with GG/GA genotype and those with AA genotype (P < 0.05).</p><p><b>CONCLUSION</b>ZNF230 gene may be associated with azoospermia, and the A316G mutation may be correlated with the serum FSH level.</p>

A Chinese autosomal dominant polycystic kidney disease family probably related to PKD2 gene / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the genetic heterogeneity of autosomal dominant polycystic kidney disease (ADPKD) in Chinese.</p><p><b>METHODS</b>Using polymerase chain reaction (PCR) and non-denatured polyacrylamide gel electrophoresis, the authors analyzed eight microsatellite markers closely linked to PKD1 or PKD2 genes respectively in a Chinese ADPKD family.</p><p><b>RESULTS</b>Seven informative markers were found in this family, including KG8, SM6, CW4 and CW2 which are tightly linked to PKD1, and D4S1563, D4S414 and D4S423 which are linked to PKD2. After the process of genotyping, the haplotypes were estimated with Cyrillic 2.0, and the linkage-based analysis suggested that the disease is not linked to PKD1 other than PKD2.</p><p><b>CONCLUSION</b>In China this non-PKD1 family is the second one, but it is the first reported PKD2 family showing the genetic heterogeneity of ADPKD in Chinese. In the family the affected mother transmits the disease and the affected members' phenotypes are eterogeneous. In addition, the existing "anticipation" and the presence of the disease in a child of this family suggest that non-PKD1 linked families may have early-onset of the disease in child.</p>

Association of APOA5 gene single nucleotide polymorphism with levels of lipids and coronary heart disease in Chinese / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To investigate the single nucleotide polymorphism 4 (SNP4) of the apolipoprotein A5 (APOA5) gene possible association with coronary heart disease(CHD) and its distribution of in Chinese Han population.</p><p><b>METHODS</b>APOA5 SNP4 genotyping was performed using polymerase chain reaction and Hae III restriction fragment length polymorphism analysis.</p><p><b>RESULTS</b>APOA5 allelic frequencies of T, C were 0.435, 0.565 and 0.374, 0.626 in CHD group and control group, respectively. There is significant difference in allele and genotype frequencies between CHD group and control group (P<0.05). The levels of plasma high density lipoprotein in CHD patients with CC genotype were higher than those in CHD patients with other genotypes (P<0.01). The frequencies of T allele and C allele in Chinese was significantly different from those in Caucasians (0.374 vs 0.663, 0.626 vs 0.337, P<0.01). The C allele was much more common in Chinese population.</p><p><b>CONCLUSION</b>The association is found between the Hae III polymorphism and CHD, There is a significant correlation between the CC genotype of the APOA5 and the levels of plasma high density lipoprotein-cholosteal in the CHD group.</p>

Mouse whole mount RNA in situ hybridization: an effective technique for analyzing gene expression / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To set up a method of analyzing gene expression profile from mouse whole embryos.</p><p><b>METHODS</b>Mouse whole mount RNA in situ hybridization(WM-ISH) of E10.5-E14 embryos was carried out by using digoxigenin-labeled Runx1 and Runx3 RNA probes and their expression profile was observed by detecting the existence and status of corresponding mRNAs in the embryonic tissues.</p><p><b>RESULTS</b>Clear hybridization signals were observed in different tissues and organs hybridized by Runx1 or Runx3 RNA probe. Different probes and ages of embryos had need of their own optimal proteinase K treatment conditions.</p><p><b>CONCLUSION</b>Mouse whole mount RNA in situ hybridization is an effective method of analyzing gene expression. It is useful for revealing whole gene expression profile and has a great potentiality in the era of functional genomics. It provides an alternative method of studies on gene expression which is at least as good as LacZ staining and immunohistochemistry. The key factor of the success to mouse whole mount RNA in situ hybridization is whether the proteinase K treatment conditions are optimal or not.</p>

Advances in the molecular mechanism of RNA interference / 中华医学遗传学杂志

This paper reviews the latest development of RNA interference(RNAi). RNA interference is the process of sequence-specific degradation of homologous mRNA triggered by double-stranded RNA. As a technically simple and an effective genetic tool which can exert effect on the expression of gene and substitute for gene knock-out technique in some degree, RNAi phenomena have been broadly validated in diverse model organisms such as Caenorhabditis elegans, Drosophila melanogaster, Arabidopsis thaliana and Neurospora crassa. Simultaneously, study on molecular mechanism of RNAi, which might be involved in the level of post-transcription, translation, genome methylation or conduction of silencing signals, is now making unceasing progress. Clear elucidation of the molecular mechanism could provide important theoretical references and powerful tools for the practical application in this field where RNAi may be put into the use of systematic gene screening, the discovery of new genes and the gene therapy for human tumor or other refractory human diseases.

Association between cholesteryl ester transfer protein gene polymorphisms and variations in lipid levels in patients with coronary heart disease / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>The Taq/B, Msp/ and I405V polymorphisms of cholesteryl ester transfer protein (CETP), an important regulatory factor of lipid metabolism, have been attracted much more attention by the researchers. In this study, we investigated the associations between these 3 polymorphisms of CETP gene and variations in plasma lipid and lipoprotein levels in patients with coronary heart disease (CHD).</p><p><b>METHODS</b>Genomic DNA was extracted from leukocytes of 203 CHD patients and 100 control subjects using the salting out method. Genotyping of the CETP gene was performed using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) techniques. Statistical analysis was conducted using the SPSS 10.0 software package.</p><p><b>RESULTS</b>The distribution of allele and genotype frequencies of the Taq/B, MspI, and I405V polymorphisms was similar in the CHD patient group and the control group. The B1B1 genotype of the Taq/B polymorphism was associated with significantly higher TC (P=0.039) and LDL-C (P=0.044) levels than the B2B2 genotype in CHD patients, and with significantly higher LDL-C (P=0.034) levels than the B2B2 genotype in controls. Homozygotes of the I405V polymorphism exhibited significantly higher HDL-C levels than VV homozygotes among control subjects (P=0.023). In male CHD patients with unambiguously assigned haplotypes, B2-M2-V/B2-M2-I patients demonstrated significantly higher HDL-C concentrations than B1-M2-V/B1-M2-I (P=0.023) and B1-M2-V/B1-M2-V patients (P=0.047).</p><p><b>CONCLUSIONS</b>Genetic variations in the CETP gene may account for a significant proportion of the differences in plasma lipid and lipoprotein concentrations among the general population. The B1B1 genotype of the Taq/B polymorphism is probably a genetic risk factor for CHD in the study population.</p>

Cloning, expression, and alternative splicing of the novel isoform of hTCP11 gene / 中国医学科学院学报

<p><b>OBJECTIVE</b>To identify a novel isoform of hTCP11 gene and investigate its expression and alternative splicing.</p><p><b>METHODS</b>According to the sequence of human ESTs which are highly homologous to hTCP11a, primers for PCR were synthesized. Then, the amplified fragments were cloned and sequenced; some methods including BLAST, ClustalW and RT-PCR were used for genomic analysis, study of alternative splicing and gene expression among multiple tissues and different testis tissues.</p><p><b>RESULTS</b>A novel isoform of hTCP11 gene was isolated. It encodes a 440 amino acid protein that is highly homologous to the mouse 566 amino acid protein which is important to sperm function because it encodes the receptor for fertilization promoting peptide (FPP). Among TCP11a, TCP11b and TCP11c, the complicated alternative splicing was found. RT-PCR analysis of RNA extracted from human tissues revealed that the gene is only expressed in fertile adult testes, but not in azoospermic patient testes, fetal testes or other human tissues.</p><p><b>CONCLUSION</b>Our results along with the mouse Tcp-11 function suggest that the isoforms of TCP11 gene play important roles in sperm function and fertility.</p>

Studies on molecular epidemiology of Y chromosome azoospermia factor microdeletions in Chinese patients with idiopathic azoospermia or severe oligozoospermia / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To determine microdeletion loci and the characteristic of Y chromosome azoospermia factor(AZF) associated with Chinese idiopathic azoospermia or severe oligozoospermia and hence to provide a theoretic basis for gene diagnosis of AZF microdeletion in Chinese infertility men.</p><p><b>METHODS</b>The subjects of this study included 134 cases of azoospermia and 118 severe oligozoospermia, and 210 healthy male controls. With multiplex PCR technique, an analysis of 15 sequence tag sites(STS) in AZFa, AZFb and AZFc microdeletion was performed.</p><p><b>RESULTS</b>No microdeletion was detected in controls whereas 13 STS loci microdeletions existed in cases, including sY84 and sY86 in AZFa; sY121, sY123, sY124, sY127, sY134 and sy133 in AZFb; sY152, sY242, sY254, sY255 and sY157 in AZFc. Five azoospermia patients were involved in AZFa microdeletions, 7 azoospermia and 3 severe oligozoospermia patients in AZFb, and 14 azoospermia and 18 severe oligozoospermia patients in AZFc. The prevalence rates of microdeletion in AZFa, AZFb and AZFc were 2.0%,4.0% and 12.7% respectively. The microdeletion rate showed statistically significant difference between the cases and controls.</p><p><b>CONCLUSION</b>This study revealed an association between the microdeletion of 13 STS loci of AZF region and the idiopathic azoospermia or severe oligozoospermia in Chinese. There is no evidence to identify the genetic polymorphism of the above STS loci. The frequency and distribution characteristic of AZF microdeletion are similar to those of Caucasians. As candidate loci the 13 STS are useful in clinical gene diagnosis for the detection of AZF microdeletion in Chinese idiopathic azoospermia and severe oligozoospermia.</p>

Study on the association of cholesteryl ester transfer protein gene mutations with the susceptibility to coronary atherosclerotic heart disease / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To determine the frequencies of 4 mutations of cholesteryl ester transfer protein (CETP) gene in Chinese population and to investigate the association of the mutations with lipid metabolism and the susceptibility to coronary atherosclerotic heart disease (CHD).</p><p><b>METHODS</b>The target fragments of CETP gene were amplified and analyzed by PCR-restriction fragment length polymorphism technique in 209 unrelated control individuals and 203 CHD patients. The test for Hardy-Weinberg equilibrium was performed using HWE program and statistical analysis was implemented in statistical package SPSS.</p><p><b>RESULTS</b>IVS14A and 451Q mutant genes were not found in either control group or patient group. The frequencies of 405V mutant allele were 0.443 and 0.413 in controls and patients, respectively, while 442G mutant gene frequencies were 0.007 and 0.025, respectively. The observed allele frequencies of I405V and D442G mutation were in accord with Hardy-Weinberg equilibrium. The frequency of 442G mutant gene in patients was significantly higher than that in controls (P=0.043). Compared with the CHD patients without D442G mutation, the 442G heterozygous CHD patients exhibited a significant increase in plasma TC and LDL-C concentration (P=0.017; P=0.041).</p><p><b>CONCLUSION</b>IVS14A and 451Q mutants of CETP gene were rare in Chinese population and 442G mutant gene was possibly one of the susceptibility factors to CHD in Chinese.</p>

Association of HMG-CoA reductase gene polymorphism with levels of lipids / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To study the distribution of ScrF1 restriction polymorphism in intron 2 of the 3-hydroxy-3-methylglutaryl coenzyme A(HMG-CoA) reductase gene in Chinese Han population and the association of the polymorphism with coronary heart disease(CHD).</p><p><b>METHODS</b>HMG-CoA reductase genotyping was performed using polymerase chain reaction-restriction fragment polymorphism.</p><p><b>RESULTS</b>HMG-CoA reductase allelic frequencies of A, a were 0.519, 0.481; 0.440, 0.560 in CHD group and control group respectively. There was no significant difference in frequencies of allele and genotype in ScrF1 polymorphism between CHD group and control group(P>0.05). However, the levels of plasma very low density lipoprotein (VLDL) and TG in CHD patients with AA genotype were higher than those in CHD patients with other genotypes(P<0.05). The frequencies of A, a alleles at ScrF1 polymorphic site were significantly different from those reported in European Caucasians (0.44 vs 0.55, 0.56 vs 0.45, P<0.05).</p><p><b>CONCLUSION</b>No direct association was found between the ScrF1 polymorphism and CHD, but there is a significant correlation between the AA genotype of the HMG-CoA reductase gene and the levels of plasma VLDL and TG in CHD group.</p>