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Objective: Acute lymphoblastic leukemia (ALL) causes the dysfunction of the systemic blood system and immune system. The etiology and predisposing factors of ALL are unknown. The suppressor of cytokine signaling 1 (SOCS1) and SOCS2 are inhibitors of cytokine signal transduction. Gene polymorphisms of SOCS1 and SOCS2 and their expressions may be related to ALL., Patients and Methods: A total of 200 ALL patients in our hospital and 200 healthy people were enrolled in ALL group and control group, respectively. Genomic deoxyribonucleic acids (DNAs) and total RNAs were extracted from the peripheral blood of each subject. Gene polymorphisms of SOCS1 at rs33977706, rs243327, and rs33932899 and those of SOCS2 at rs3816997 were amplified by polymerase chain reaction (PCR) and sequenced. Besides, the expression levels of SOCS1 and SOCS2 in ALL patients were detected by real-time fluorescence quantitative PCR., Results: The frequency of the allele C of SOCS1 rs33977706 in ALL group was lower than that in the control group, displaying a significant difference between the two groups (p=0.015). The frequency of allele A of SOCS2 rs3816997 was notably higher in ALL group than that of the control group (p=0.000). In addition, the frequency of CA genotype of SOCS1 rs33977706 in ALL group was markedly lower than that in the control group, showing a significant difference (p=0.000). ALL group had remarkably higher frequencies of AA genotype of SOCS2 rs3816997 (p=0.000) and ACC haplotype of SOCS gene (p=0.000), and lower frequencies of ATG (p=0.026) and CCC (p=0.006) haplotypes. The two loci, SOCS1 rs33932899 and SOCS1 rs243327, were linked to each other (D'=0.781). Moreover, the expression level of SOCS1 in ALL group was lower than that in the control group, in which the expression of the CT genotype of SOCS1 rs243327 was relatively higher (p=0.021). SOCS2 level was lower in ALL group. Particularly, SOCS2 level in ALL patients carrying AC genotype was lower than those carrying AA and CC genotypes (p=0.000). ALL patients carrying CT genotype of SOCS1 rs243327 had shorter period of agranulocytosis (p=0.000), a lower ratio of bone marrow primitive/immature cells (p=0.001), and a higher hemoglobin (Hb) level in blood (p=0.000). The ratio of bone marrow primordial/immature cells was lower in ALL patients with AC genotype of SOCS2 rs3816997 (p=0.038)., Conclusions: The expression levels of SOCS1 and SOCS2 are prominently related to ALL, and their polymorphisms are associated with the susceptibility to ALL.

Maturity-onset diabetes of the young (MODY) is characterized by the onset of diabetes before the age of 25 years, positive family history, high genetic predisposition, monogenic mutations, and an autosomal dominant mode of inheritance. Here, we aimed to investigate the mutations and to characterize the phenotypes of a Han Chinese family with early-onset maternally inherited type 2 diabetes. Detailed clinical assessments and genetic screening for mutations in the HNF4α, GCK, HNF-1α, IPF-1, HNF1β, and NEUROD1 genes were carried out in this family. One HNF4A mutation (p.T130I) and two HNF1A polymorphisms (p.I27L and p.S487N) were identified. Mutation p.T130I was associated with both early-onset and late-onset diabetes and caused downregulated HNF4A expression, whereas HNF1A polymorphisms p.I27L and p.S487N were associated with the age of diagnosis of diabetes. We demonstrated that mutation p.T130I in HNF4A was pathogenic as were the predicted polymorphisms p.I27L and p.S487N in HNF1A by genetic and functional analysis. Our results show that mutations in HNF4A and HNF1A genes might account for this early-onset inherited type 2 diabetes.

As a major cardiovascular risk factor for stroke, coronary artery disease, heart failure and end-stage renal disease, hypertension affects approximately one billion people and causes large economic burden worldwide. Cytochrome P450 3A5 (CYP3A5), belonging to the CYP3A subfamily, has been implicated in the regulation of blood pressure and may serve as a potential risk factor for the development of hypertension. Increased CYP3A5 activity could cause sodium and water retention by affecting the metabolism of cortisol in the kidneys. Furthermore, polymorphic CYP3A5 genotypes have been shown to cause differences in blood pressure response to antihypertensive drugs. Several studies have investigated the role of CYP3A5 in blood pressure response to amlodipine. However, recent data on the role of CYP3A5 in hypertension development and treatment are inconsistent. This review summarizes what is known regarding the relationship of CYP3A5 with hypertension, discusses the limitations in present studies, highlights the gaps and directs research to this field.

Background: The -308 G/A polymorphism in the tumor necrosis factor (TNF) gene has been implicated in the risk of acne vulgaris, but the results are inconclusive. The present meta-analysis aimed to investigate the overall association between the -308 G/A polymorphism and acne vulgaris risk., Methods: We searched in Pubmed, Embase, Web of Science and CNKI for studies evaluating the association between the -308 G/A gene polymorphism and acne vulgaris risk. Data were extracted and statistical analysis was performed using STATA 12.0 software., Results: A total of five publications involving 1553 subjects (728 acne vulgaris cases and 825 controls) were included in this meta-analysis. Combined analysis revealed a significant association between this polymorphism and acne vulgaris risk under recessive model (OR = 2.73, 95% CI: 1.37-5.44, p = 0.004 for AA vs. AG + GG). Subgroup analysis by ethnicity showed that the acne vulgaris risk associated with the -308 G/A gene polymorphism was significantly elevated among Caucasians under recessive model (OR = 2.34, 95% CI: 1.13-4.86, p = 0.023)., Conclusion: This meta-analysis suggests that the -308 G/A polymorphism in the TNF gene contributes to acne vulgaris risk, especially in Caucasian populations. Further studies among different ethnicity populations are needed to validate these findings.

Genomic instability caused by telomere erosion is an important mechanism of tumorigenesis. p53 plays a key role in cellular senescence and/or apoptosis associated with telomere erosion which positions p53 as a guard against tumorigenesis. The present study was undertaken to investigate the potential interactions between p53 functional mutations, polymorphisms, allelic loss and telomere erosion in 126 breast tumor patients and 68 esophageal cancer patients. Telomere length (TL) was measured by real-time quantitative PCR. Somatic mutations, polymorphisms and allelic loss in the TP53 gene were detected by direct sequencing of both tumor and normal tissue samples. Our results showed that telomeres were significantly shorter in tumors with somatic p53 mutations compared with tumors with wild-type p53 in both breast tumors (P=0.007) and esophageal cancer (P=0.001). Telomeres of patients with minor genotype CC of rs12951053 and GG of rs1042522 were significantly shorter compared to patients with other genotypes of this single nucleotide polymorphism in esophageal cancer tissue. Furthermore, TP53 allelic loss was detected and significantly associated with somatic mutations in both types of tumor tissues. These findings suggest that somatic p53 mutations, rs12951053 genotype CC and rs1042522 genotype GG contribute to erosion of telomeres, and TP53 allelic loss may be one of the representations of chromosomal instability caused by telomere erosion combined with somatic p53 mutations. These results support that the TP53 gene has a strong interaction with TL erosion in tumorigenesis.

Purpose: The GNAS1 gene is linked to proapoptotic signaling and correlates closely with clinical outcomes in many human cancers. The aim of this study was to evaluate whether the T393C polymorphism of the GNAS1 gene could be used as a chemotherapy sensitivity and prognosis predictive marker of advanced non-small-cell lung cancer (NSCLC) treated with gemcitabine plus platinum (GP)., Methods: In this study, we performed the PCR-restriction fragment length polymorphism assay to examine the genotypes of the GNAS1 T393C polymorphism in 131 peripheral blood DNA specimens from advanced NSCLC patients with GP treatment., Results: The frequencies of the CC, CT, and TT genotypes in 131 advanced NSCLC cases were 25.2, 47.4, and 26.7%, respectively. The favorable TT genotype was significantly correlated with better overall survival (OS; P < 0.05) and longer progress-free survival (PFS; P < 0.05) compared with the CT or CC genotype. In the multivariate Cox proportional hazards model, the GNAS1 T393C polymorphism was independently associated with overall survival after adjusting the clinicopathological factors (P < 0.05)., Conclusions: This study suggests that the TT genotype of the GNAS1 T393C polymorphism could be an independent prognostic marker to predict chemotherapy sensitivity, favorable OS and PFS in advanced NSCLC patients with GP treatment.

Introduction: Human height is a highly heritable trait considered as an important factor for health. There has been limited success in identifying the genetic factors underlying height variation. We aim to identify sequence variants associated with adult height by a genome-wide association study of copy number variants (CNVs) in Chinese., Methods: Genome-wide CNV association analyses were conducted in 1,625 unrelated Chinese adults and sex specific subgroup for height variation, respectively. Height was measured with a stadiometer. Affymetrix SNP6.0 genotyping platform was used to identify copy number polymorphisms (CNPs). We constructed a genomic map containing 1,009 CNPs in Chinese individuals and performed a genome-wide association study of CNPs with height., Results: We detected 10 significant association signals for height (p<0.05) in the whole population, 9 and 11 association signals for Chinese female and male population, respectively. A copy number polymorphism (CNP12587, chr18:54081842-54086942, p = 2.41 × 10(-4)) was found to be significantly associated with height variation in Chinese females even after strict Bonferroni correction (p = 0.048). Confirmatory real time PCR experiments lent further support for CNV validation. Compared to female subjects with two copies of the CNP, carriers of three copies had an average of 8.1% decrease in height. An important candidate gene, ubiquitin-protein ligase NEDD4-like (NEDD4L), was detected at this region, which plays important roles in bone metabolism by binding to bone formation regulators., Conclusions: Our findings suggest the important genetic variants underlying height variation in Chinese.

Human longevity has been associated with mitochondrial DNA (mtDNA) coding region polymorphisms, as well as the C150T polymorphism in the non-coding region in previous studies especially in Europeans. This study investigated the potential association between the mtDNA C150T polymorphism and longevity in a Han Chinese population. Leukocyte mtDNAs from two groups of a Han Chinese population living in Dujiangyan city of Sichuan province, including 556 longevous individuals (90-108 years-old) and 403 unrelated controls, were analyzed and mtDNA haplogroups were determined by sequencing control regions and restriction fragment length polymorphisms (RFLPs) in coding regions. Our results did not show a universal association between the mitochondrial C150T polymorphism and longevity in this population. Even when mtDNA haplogroups defined by C150T and gender were taken into account, there was no significant association with longevity. In conclusion, the mtDNA C150T polymorphism could not present an accumulation in an elderly Han Chinese population. Previous association studies might have been influenced by nuclear DNA and/or environment factors., (Copyright © 2011 Elsevier Inc. All rights reserved.)

Background: Several investigators have employed high throughput mitochondrial sequencing array (MitoChip) in clinical studies to search mtDNA for markers linked to cancers. In consequence, a host of somatic mtDNA mutations have been identified as linked to different types of cancers. However, closer examination of these data show that there are a number of potential pitfalls in the detection tumor-specific somatic mutations in clinical case studies, thus urging caution in the interpretation of mtDNA data to the patients. This study examined mitochondrial sequence variants demonstrated in cancer patients, and assessed the reliability of using detected patterns of polymorphisms in the early diagnosis of cancer., Methods: Published entire mitochondrial genomes from head and neck, adenoid cystic carcinoma, sessile serrated adenoma, and lung primary tumor from clinical patients were examined in a phylogenetic context and compared with known, naturally occurring mutations which characterize different populations., Results: The phylogenetic linkage analysis of whole arrays of mtDNA mutations from patient cancerous and non-cancerous tissue confirmed that artificial recombination events occurred in studies of head and neck, adenoid cystic carcinoma, sessile serrated adenoma, and lung primary tumor. Our phylogenetic analysis of these tumor and control leukocyte mtDNA haplotype sequences shows clear cut evidence of mixed ancestries found in single individuals., Conclusions: Our study makes two prescriptions: both in the clinical situation and in research 1. more care should be taken in maintaining sample identity and 2. analysis should always be undertaken with respect to all the data available and within an evolutionary framework to eliminate artifacts and mix-ups.

Polymorphisms in four regions of the bovine prion protein gene (PRNP) confer susceptibility to bovine spongiform encephalopathy (BSE). These polymorphisms include a 23-bp insertion/deletion (indel) in the promoter region, a 12-bp indel in intron 1, an octapeptide repeat or 24-bp indel in the open reading frame, and a single nucleotide polymorphism (SNP) in the coding region. In this study, we investigated the frequency distributions of genotypes, alleles, and haplotypes at these indel sites in 349 native Chinese cattle and sequence variants in 50 samples. Our results showed that cattle in southern China have low frequencies of the 12-bp deletion allele and the 23-bp deletion / 12-bp deletion haplotype, which have been suggested to be relevant to BSE susceptibility. Interestingly, a significant difference was observed between BSE-affected cattle and healthy Chinese cattle in the 12-bp indel polymorphism. A total of 14 SNPs were discovered in the coding region of PRNP in Chinese cattle. Three of these SNPs were associated with amino acid changes (K3T, P54S, and S154N). The E211K substitution that was recently reported in the US atypical BSE case was not detected in this study.

Recent studies have proposed that susceptibility to chronic obstructive pulmonary disease (COPD) might be related with the polymorphisms of some genes encoding antioxidant enzymes, such as heme oxygenase-1 (HOX-1) and microsomal epoxide hydrolase (mEPH). We examined these polymorphisms in 256 patients with COPD and 266 healthy smokers from Han population in Southwest China. The frequencies of each allele were compared both individually and in combination between patients and controls. Polymorphisms of HOX-1 gene could be grouped into three classes: S (or=32 repeat). The allele frequencies of class L and the genotypic frequencies of the group with L were significantly higher in COPD than in controls. Our findings also showed that the proportion of slow mEPH activity was significantly higher in COPD than in controls. Conversely, the proportion of fast mEPH activity was significantly lower in COPD. In combined analysis, the frequency of the individuals having at least one L allele in the HOX-1 gene promoter and slow or very slow activity genotype for mEPH was higher in COPD than in control. Genetic polymorphisms in HOX-1 and mEPH genes are associated with the development of COPD in Southwest China.

Background: Recent studies have suggested that susceptibility to chronic obstructive pulmonary disease (COPD) might be related to the length polymorphism of (GT)(n) repeat in the 5'-flanking region of heme oxygenase-1 (HOX-1) gene. However, there has been no research about the relationship between the polymorphism of HOX-1 gene and severity of COPD., Methods: The polymorphism of HOX-1 gene in 452 patients with COPD from Han population in Southwest China was analysed by fragment analysis. The frequencies of the HOX-1 genotype were compared with the stage of COPD of each patient., Results: The HOX-1 genotypes were classified into two groups: group I were individuals with class L allele (the number of GT = 32 repeats), and group II were those without class L allele (the number of GT < 32 repeats). The genotypic frequency of the HOX-1 group I was significantly higher than group II in the very severe COPD patients (36.8% vs 22.4%, P < 0.01, OR = 2.0, 95% CI 1.3 - 3.1), while the genotypic frequency of the HOX-1 group II was lower in the mild COPD (16.0% vs 26.0%, P = 0.02, OR = 0.5, 95% CI 0.3 - 0.9). However, in moderate and severe stages COPD, there were similar genotypic frequencies between HOX-1 group I and group II., Conclusions: Genetic polymorphism in HOX-1 is associated with the severity of COPD in Southwest China. COPD patients with class L allele may be susceptible to develop very severe COPD. Conversely, the COPD patients without class L allele may be more easily stabilized on mild COPD.

This study was aimed to investigate the molecular genetic basis and serological phenotype of Rh weak D type 15 individuals. Samples were identified by serological tests and genotyped by sequence specific primer-PCR (SSP-PCR), and were sequenced to detect the changes of all ten RHD exons. The number of gene RHD was detected through SSP-PCR. The results showed that in tested individuals of weak D type confirmed by the IAT, 18 cases (56% in weak D) were weak D type 15. Rh factors found in 2 weak D type 15 individuals (11%) were C+c+E+e; Rh factors found in 2 weak D type 15 individuals (11%) were C+c+E-e+; others (78%) were c-c+E+e+. The results by serological tests were consistent with the results genotyped by PCR-SSP method. In all 18 samples, the sequencing result revealed a gene mutation 845G > A at the exon 6 of the RHD and the point mutation changed amino acid G282D of the RhD polypeptide. The zygosity test demonstrated that 2 out of 18 weak D type 15 individuals were RHD(+)/RHD(+) homozygous (two DCe/DcE), 16 cases were RHD(+)/RHD(-) heterozygous (two DCe/dce and fourteen DcE/dce). It is concluded that Weak D type 15 is predominant in weak D individuals of Chinese Han Nationality, and most of them are heterozygous with various RH haplotypes.

Objective: To explore the genetic susceptibility of children to vitamin D deficiency rickets through studying the association between Vitamin D receptor (VDR) gene polymorphism and vitamin D deficiency rickets., Methods: One hundred and fifty-nine children (100 boys and 59 girls, aged 0 to 2 years), with new-onset vitamin D deficiency rickets were enrolled. The patients sampled from a community of Jiamusi City, Heilongjiang Province. Seventy-eight healthy age-matched children (46 boys and 32 girls) were used as the controls. VDR gene polymorphism (cleaved by restriction endonuclease Fok I) was analyzed by polymerase chase reaction-restriction fragment length polymorphism (PCR-RFLP). The frequencies of the VDR genotype and allele were compared between the two groups., Results: The frequencies of FF, Ff and ff genotypes were 37%, 51% and 12% in the Rickets group, and 18%, 55% and 27% in the Control group. A significant difference was found in the frequency distribution of the VDR genotype between the two groups (chi(2)(0.01(2))=9.210, chi(2)=13.3880, P < 0.01). In the Rickets group, f allele frequency was lower (37% vs 54%), while the F allele was more common than the Control group (63% vs 46%)., Conclusions: There is an association between the VDR gene Fok I polymorphism and vitamin D deficiency rickets. The individuals with the F allele are more susceptible to vitamin D deficiency rickets.

To study the genetic polymorphism of HPA 1-16 platelet antigen alleles among unrelated volunteer donors and establish a typed platelet donor panel in Handan, typing was perfomed by polymerase chain reaction using sequence-specific primers (SSP-PCR); 148 random unrelated blood donors in Handan were genotyped for each of the HPA 1-16 antigen. The gene frequencies were analyzed and the genetype frequencies were determined by direct counting, and these data were compared with HPA distribution among various population by the chi-square test. The results indicated that HPA-1a, 2a, 4a-14a, 16a genes were found among the 16 HPAs in every sample tested. Monomorphic HPA-4a, 7a-14a, 16a were found in the samples. For HPA-1, 2, 5 and 6, a/a homozygosity was predominant with frequencies of 0.9595, 0.8108, 0.9865, 0.9797, respectively, and none of HPA b/b was found in the samples. HPA-1b, 2b, 5b, 6b were rarely found among subjects. HPA-15 had the greatest heterozygosity with a gene frequency of 0.2230, 0.5270, 0.2500 for HPA15a/15a, HPA15a/15b, HPA15b/15b, respectively. HPA-3 showed the second greatest heterozygosity with a gene frequency of 0.3851, 0.5135, 0.1014 for HPA3a/3a, HPA3a/3b, HPA3b/3b, respectively. HPA genotype frequencies showed a good fit to Hardy-Weinberg equilibrium. HPA1-5 gene frequencies for Chinese people in Handan were consistent with those of Chinese people in Shijiazhuang (P > 0.05). Among the HPA1-13, -15, the frequencies of HPA-1, -2, -6 for Chinese people in Handan differed appreciably from those for Chinese people in Taiwan (P < 0.05), others were similar to those of Chinese people in Taiwan. Among the HPA 1 - 8, a similarity was noted between Chinese people in Handan and Koreans (P > 0.05), except for HPA-3. Frequencies of HPA-1, -2, -5 significantly were differed from those in African Americans, as compared with HPA 1-5 (P < 0.05). Comparison of gene frequencies from HPA-1 and -5 showed significant differences between Chinese people in Handan and people in UK (P < 0.05). It is concluded that HPA-2, -3, -5, -15 of people in Western region of China have polymorphism, incompatible frequency of HPA antigen distribution is higher, which inevitably results in the increase of immunologic exposure, therefore attention must be paid to the importance of HPA-2, -3, -5, -15 in clinical disorders. This study for the first time completely analyses HPA1-16 gene frequencies in China, and provides data for establishing a typed platelet donor panel in Handan, China.

Traditionally the cluster of swine leukocyte antigen (SLA) was typed by serological, cytological and biochemical methods. Many special molecular typing methods have been developed with the progress of molecular biological technology, such as PCR-RFLP, PCR-SSCP , MS and DNA sequencing. Here we discussed the advantages and disadvantages of each method based on the polymorphic and conservative (from the functional aspect, such as supertype and supermotif) characteristics of SLA, and illustrated the development of typing for SLA in the future. In addition, we pointed out the editorial mistakes about the serological haplotype of SLA in reference book and emphasized that the accurate polymorphism of SLA-DQB gene must be based on the cloning sequencing.

An atypical allele (ALDH2*2) in low K(m) aldehyde dehydrogenase (ALDH2), which is highly prevalent in Asians, may influence drinking behavior because of higher production of acetaldehyde in the liver. High alcohol sensitivity such as flushing after drinking has been shown to be mainly due to the atypical ALDH2 genotypes. The atypical allele is associated with alcohol-induced liver injury and some cancers. Recently, the researches on the polymorphisms not only in the gene itself but also its frequencies in different Asian populations have been made great progress. Three factors, including different sex, age and geography, were also analyzed with the genotypes of ALDH2 in Chinese populations.

Objective: To investigate the relationship between the polymorphism of beta 2 adrenergic receptor (beta 2 AR) at loci 16, 27 and the nocturnal asthma phenotype., Methods: Forty-nine asthmatic patients were divided into nocturnal asthmatic group (n = 25) and non-nocturnal asthmatic group(n = 24) by their peak expiratory flow rates (PEFR). The genotypes at loci 16, 27 of beta 2 AR were delineated by PCR product sequencing. Then the relationships of beta 2 AR genotypes with the PEFR, FEV1 and the situation of drug use in the two groups were analyzed., Results: By the criteria of overnight decrements in PEFR, the nocturnal asthma group had a mean overnight decrement in PEFR of 33.6%, compared to 7.0% for the non-nocturnal asthma group (P < 0.001). The mean values of daytime baseline percent predicted forced expiratory volume in 1 s (FEV1) were 73.7% and 85.8% for the nocturnal and non-nocturnal cohorts, respectively (P < 0.001). The frequency of the Gly16 allele was 56.0% in the nocturnal group, compared to 22.9% in the non-nocturnal group (P < 0.05). The results from comparison of the two cohorts as to homozygosity for Gly16, homozygosity for Arg16, or heterozygosity were also consistent with the segregation of Gly16 with nocturnal asthma. There was no significant difference in the frequency of polymorphisms at locus 27 (Gln27 or Glu27)., Conclusion: The Gly16 polymorphism of beta 2 AR appears to be associated with nocturnal asthma.

To study the mitochondrial DNA (mtDNA) polymorphisms in a total of 232 individuals from five ethnic populations (Daur, n=45; Ewenki, n=47; Korean, n=48; Mongolian, n=48; Oroqen, n=44) in northern China, we analyzed the control region sequences and typed for a number of characteristic mutations in coding regions (especially the region 14576-16047), by direct sequencing or restriction-fragment-length-polymorphism (RFLP) analysis. With the exception of 14 individuals belonging to the European-specific haplogroups R2, H, J, and T, the mtDNAs considered could be assigned into the East Asian-specific haplogroups described recently. The polymorphisms in cytochrome b sequence were found to be very informative for defining or supporting the haplogroups status of East Asian mtDNAs in addition to the reported regions 10171-10659 and 14055-14590 in our previous study. The haplogroup distribution frequencies varied in the five ethnic populations, but in general they all harbored a large amount of north-prevalent haplogroups, such as D, G, C, and Z, and thus were in agreement with their ethnohistory of northern origin. The two populations (Ewenki and Oroqen) with small population census also show concordant features in their matrilineal genetic structures, with lower genetic diversities observed.

The polymorphism of a gene or a locus is studied with increasing frequency by multiple laboratories or the same group at different times. Such practice results in polymorphism being revealed by different samples at different regions of the locus. Tests of neutrality have been widely conducted for polymorphism data but commonly used statistical tests cannot be applied directly to such data. This article provides a procedure to conduct a neutrality test and details are given for two commonly used tests. Applying the two new tests to the chemokine-receptor gene (CCR5) in humans, we found that the hypothesis that all mutations are selectively neutral cannot explain the observed pattern of DNA polymorphism.

Previous studies have shown that mitochondrial DNA (mtDNA) 5178 adenine/cytosine (5178A) polymorphism, which is one of the haplogroup-specific mutations for mtDNA haplogroup D, was apparently associated with aging and longevity in humans. We genotyped the 5178A in 293 samples representing three age groups (Old, n=95; Young, n=103; and Infant, n=95) from Yunnan Province, China. The distribution frequency of the 5178A in the Old samples (16.84%) is slightly higher than in those of the Young (13.59%) and Infant (15.79%), but the frequency difference between the age groups is far from being statistically significant ( P>0.05). Our results fail to support the suggestion of association between mtDNA 5178A (or haplogroup D) and longevity.

Mitochondrial DNAs (mtDNA) from 21 yaks (Bos grunniens) were assayed for restriction fragment length polymorphisms by using 20 restriction endonucleases, six of which (AvaI, AvaII, BgIII, EcoRI, HindIII, and HpaI) detected polymorphism. Four different mtDNA haplotypes were identified. Combining this with previous reports about the mtDNA RFLPs of B. indicus and B. taurus, there are obvious differences in mtDNA polymorphism between the yak and other Bos species. We estimated that the divergence times between the ancestor of B. grunniens and the ancestor of B. taurus or B. indicus were about 1.2-2.2 and 1.01-2.02 million years ago, respectively.

To characterize the mitochondrial DNA (mtDNA) variation in Han Chinese from several provinces of China, we have sequenced the two hypervariable segments of the control region and the segment spanning nucleotide positions 10171-10659 of the coding region, and we have identified a number of specific coding-region mutations by direct sequencing or restriction-fragment-length-polymorphism tests. This allows us to define new haplogroups (clades of the mtDNA phylogeny) and to dissect the Han mtDNA pool on a phylogenetic basis, which is a prerequisite for any fine-grained phylogeographic analysis, the interpretation of ancient mtDNA, or future complete mtDNA sequencing efforts. Some of the haplogroups under study differ considerably in frequencies across different provinces. The southernmost provinces show more pronounced contrasts in their regional Han mtDNA pools than the central and northern provinces. These and other features of the geographical distribution of the mtDNA haplogroups observed in the Han Chinese make an initial Paleolithic colonization from south to north plausible but would suggest subsequent migration events in China that mainly proceeded from north to south and east to west. Lumping together all regional Han mtDNA pools into one fictive general mtDNA pool or choosing one or two regional Han populations to represent all Han Chinese is inappropriate for prehistoric considerations as well as for forensic purposes or medical disease studies.

Phylogenetic relationships among Asian and European pig breeds were assessed using 1036 bp of mitochondrial DNA (mtDNA) D-loop sequences. An unweighted pair-group method with arithmetic mean (UPGMA) tree was constructed on the basis of maximum likelihood distances using sequences determined for three Cheju (Korea), 11 Chinese, one Westran (Australian feral origin) and two European pigs (Berkshire and Welsh), and also published sequences for four Japanese (including two Wild Boars), one Yucatan miniature, five European (including Large White, Landrace, Duroc, Swedish and Wild Boar) and two Meishan pigs. The Colombian collared peccary (Tayassu tajacu) sequence was also determined and used as an outgroup. The maximum parsimony with heuristic search method was used to determine bootstrap support values. Asian-type pigs clustered together (bootstrap support 33%), but were separate from European-type pigs that also clustered together (93%). The Westran pig, derived from the feral descendants of pigs inhabiting Kangaroo Island of South Australia, clustered with Asian pigs, demonstrating Asian origin of their mitochondria. Berkshire and Large White clustered with Asian pigs, indicating that Asian pigs were involved in the development of these breeds. Our findings clearly demonstrate that pigs indigenous to China, Korea and Japan are only recently diverged from each other and distinctly different from European-type pigs. European pig breeds consist of pigs with mitochondria of Asian and non-Asian type, some of which were formed from closely related maternal ancestors, if not from a single ancestor.

There is strong relationship between melanocortin-1 receptor (MC1R) gene variants and human hair color and skin type. Based on a sequencing study of MC1R gene in 50 individuals from the Uygur, Tibetan, Wa and Dai ethnic populations, we discuss the occurrence of 7 mc1r variants consisting of 5 nonsynonymous sites (Val60Leu, Arg67Gln, Val92Met, Arg163Gln and Ala299Val) and 2 synonymous sites (C414T and A942G), among which C414T and Ala299Val were reported for the first time. Confirmation and analysis were also made of 122 individuals at three common point mutations (Val92Met, Arg163Gln, A942G) using PCR-SSCP. The frequency of Arg163Gln variant varies in the four ethnic populations, with percentage of 40%, 85.0%, 66.2% and 72.7%, respectively, while those of Val92Met and A942G are roughly similar in these four populations. The different environments, migration and admixture of various ethnic groups in China might have impact on the observed frequency of Arg163Gln.

Mitochondrial DNA control region segment I sequences and melanocortin 1 receptor (MC1R) gene polymorphism were examined in ethnic populations in the silk road region of China. Both the frequencies of the MC1R variants and the results of mtDNA data in this region presented intermediate values between those of Europe and East and Southeast Asia, which suggested extensive gene admixture in this area and was in general agreement with previous studies. Phylogenetic analysis of the ethnic populations in the Silk Road region that based on mtDNA data didn't show expected cluster pattern according to their ethnogenesis. We suspect that a high migration rate in female among these closely related populations and other three demographic events might account for it.

We examined protein polymorphism of 20 native pig breeds in China and 3 introduced pig breeds. Thirty loci have been investigated, among which six loci were found to be polymorphic. Especially, the polymorphism of malate dehydrogenase (MDH), adenylate kinase (AK), and two new alleles of adenosine deaminase (ADA) had not been reported in domestic pigs and wild pigs. The percentage of polymorphic loci (P), the mean heterozygosity (H), and the mean number of alleles (A) are 0.200, 0.065, and 1.300, respectively. The degree of genetic variability of Chinese pigs as a whole was higher than that of goats, lower than that of cattle and horses, and similar to that of sheep. Using the gene frequencies of the 30 loci, Nei's genetic distance among the 20 native breeds in China and 3 introduced pig breeds was calculated by the formula of Nei. The program NEIGHBOR in PHYLIP 3.5c was chosen to construct an UPGMA tree and a NJ tree. Our results show that, of the total genetic variation found in the native pig breeds in China, 31% (0.31) is ascribable to genetic differences among breeds. About 69% of the total genetic variation is found within breeds. Most breeds are in linkage disequilibrium. The patterns of genetic similarities between the Chinese native pig breeds were not in agreement with the proposed pig type classification.

Mitochondrial DNAs (mtDNAs) of 138 samples from 11 domestic goose breeds in China were investigated by digesting, with 19 restriction endonucleases. Of 19 enzymes used, seven (Bcl I, Dra I, Eco RV, Hae II, Hinc II, Kpn I, Sac I) detected polymorphic patterns. By combining 27 restriction morphs, 138 individuals were classified into 6 mtDNA haplotypes. Phylogenetic tree was constructed by using UPGMA. There was no shared haplotype between Yili breed and the other 10 breeds. Genetic distance and UPGMA tree also suggested that Yili breed and other breeds came from different ancestors. Yili breed originated from Anser anser and other 10 breeds originated from Anser cygnoides. Restriction morphs digested with 4 enzymes (EcoRV, Hae II, Hinc II and Kpn I) could be used as maternal genetic markers to distinguish the two types of domestic geese. Mitochondrial DNA polymorphism was observed in the ten breeds of Anser cygnoides. Nucleotide diversity (pi), genetic distance between the two types and the average genetic distance among the ten breeds were estimated to be 0.025%, 0.266%, 0.029%, respectively. The breeds with white plume were affected by founder effect when they were formed. Swan domestic geese, Anser cygnoides domesticus, in China might come from two different populations of Anser cygnoides at two different places.

Two different forms of Chinese pangolins can be recognized according to the color of their scales, i.e., brown and dusky. We analyzed mitochondrial DNA (mtDNA) purified from the livers of seven dusky and six brown Chinese pangolins from the same locality, using cleavage patterns from 19 restriction enzymes. From the 19 6-bp recognition enzymes used, 51-56 sites were observed. By combining the cleavage patterns for each enzyme, the 13 samples were classified into four restriction types: two in dusky and two in brown Chinese pangolins. The estimated number of nucleotide substitutions per site in dusky and brown types is 0.002, and that between dusky and brown types is 0.012. Divergence between brown and dusky forms began 0.6 Myr ago, provided the mean rate of sequence divergence is 0.02 per Myr in mtDNA. Our results suggest that there is considerable divergence in Chinese pangolins, and brown and dusky Chinese pangolins may be quite different forms or, at least, belong to different maternal groups.

mtDNA from thirteen monkeys of five species (Macaca mulatta, M. nemestrina, M. assamensis, M. thibetana, M. arctoides) of the genus Macaca was analyzed with ten restriction enzymes, and compared with that of Japanese monkey (Macaca fuscata). Eight restriction types were observed among thirteen samples. There was extensive polymorphism in M. mulatta. The estimated number of nucleotide substitutions per site in M. mulatta is 0.012, and between these six species ranges from 0.016 to 0.091. Molecular phylogenetic tree of the mtDNA was constructed based on the genetic distance (P). The six species were divided into four groups: M nemestrina, M. arctoides, M. assamensis and M. thebitana, M. mulatta and M. fuscata. Our results support Fooden's (1976) classification of the genus Macaca into four species groups on the basis of morphologic data. Divergence times of the six species of the genus Macaca were also estimated on the mean rate of sequences divergence of 0.02 per million years in mtDNA.