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Abstract: Epidermolytic palmoplantar keratoderma (EPPK) is the most frequent form of such keratodermas. It is inherited in an autosomal dominant pattern and is clinically characterized by diffuse yellowish thickening of the skin on the palms and soles with erythematous borders during the first weeks or months after birth. EPPK is generally caused by mutations of the KRT9 gene. More than 26 KRT9 gene mutations responsible for EPPK have been described (Human Intermediate Filament Database, www.interfil.org), and many of these variants are located within the highly-conserved coil 1A region of the α-helical rod domain of keratin 9. Unfortunately, there is no satisfactory treatment for EPPK. Thus, prenatal molecular diagnosis or pre-pregnancy diagnosis is crucial and benefits those affected who seek healthy descendants. In the present study, we performed amniotic fluid-DNA-based prenatal testing for three at-risk pregnant EPPK women from three unrelated southern Chinese families who carried the KRT9 missense mutations p.Arg163Trp and p.Arg163Gln, and successfully helped two families to bear normal daughters. We suggest that before the successful application of preimplantation genetic diagnosis (PGD), and noninvasive prenatal diagnosis of EPPK that analyzes fetal cells or cell-free DNA in maternal blood, prenatal genetic diagnosis by amniocentesis or chorionic villus sampling (CVS) offers a quite acceptable option for EPPK couples-at-risk to avoid the birth of affected offspring, especially in low- and middle-income countries. [Copyright &y& Elsevier]

Background The majority of non-syndromic hearing loss (NSHL) patients result from causative mutations in GJB2 , SLC26A4 and mitochondrial 12S rRNA genes. Accurate detection of these genetic mutations is increasingly recognized for its clinical significance to reduce incidence and guide individual treatment of NSHL. Current methods for clinical practice are labor intensive, expensive or of low sensitivity. Methods Genomic DNA from 7 newborns not passing the hearing screening and 94 newborns passing the hearing screening were analyzed for the common mutations using high resolution melting analysis (HRMA) and Sanger sequencing. Results Our newly developed HRMA allowed the hot-spot mutations of GJB2 c.176_191del16 and c.235delC, SLC26A4 IVS7-2A > G and mitochondrial 12S rRNA 1494C > T and 1555A > G to be detected by melting profiles based on small amplicons. HRMA can distinguish different content mutant DNA from wildtype DNA, with a detection limit of 5%. Moreover, the results were highly concordant between HRMA and Sanger sequencing. Conclusions These results indicate that HRMA could be used as a routine clinical method for prenatal diagnosis and newborn genetic screening due to its accuracy, sensitivity, and rapid, low-cost and less laborious workflows. [ABSTRACT FROM AUTHOR]

SNaPshot minisequencing is a rapid and robust methodology based on a single base extension with a labeled ddNTP. The present study detected 15 selected SNPs in the mitochondrial DNA (mtDNA) control and coding regions by minisequencing methodology using SNaPshot for forensic purpose. The samples were collected from 99 unrelated individuals of the Yi ethnic minority group in Yunnan Province. We have predominantly found high-frequency transitions (91.7%) and a significantly lower frequency of transversions (8.3%). The nt152, 489, 8701, 10,398, 16,183, and 16,362 loci were highly polymorphic, while the nt231, 473 and 581 loci were not polymorphic in the studied population. Based on these 15 SNPs, a total of 28 mtDNA haplotypes were defined in 99 individuals with the haplotype diversity of 0.9136. Also, we compared the mtDNA sequences of Yi group and other 9 populations worldwide and drew a Neighbor-Joining tree based on the shared 12 mtDNA SNP loci, which demonstrated a close relationship between Yi and Bai groups. In conclusion, the analysis of the 15 selected SNPs increases considerably the discrimination power of mtDNA. Moreover, the SNaPshot minisequencing method could quickly detect mtDNA SNPs, and is economical and sensitive. The set of selected 15 SNPs is highly informative and is capable for anthropology genetic analysis. [ABSTRACT FROM AUTHOR]

Abstract: Mutation-based molecular diagnostics of autosomal dominant polycystic kidney disease (ADPKD) is complicated by genetic and allelic heterogeneity, large multi-exon genes, and duplication sequences of PKD1. Recently, targeted resequencing by pooling long-range polymerase chain reaction (LR-PCR) amplicons has been used in the identification of mutations in ADPKD. Despite its high sensitivity, specificity and accuracy, LR-PCR is still complicated. We performed whole-exome sequencing on two unrelated typical Chinese ADPKD probands and evaluated the effectiveness of this approach compared with Sanger sequencing. Meanwhile, we performed targeted gene and next-generation sequencing (targeted DNA-HiSeq) on 8 individuals (1 patient from one family, 5 patients and 2 normal individuals from another family). Both whole-exome sequencing and targeted DNA-HiSeq confirmed c.11364delC (p.H3788QfsX37) within the unduplicated region of PKD1 in one proband; in the other family, targeted DNA-HiSeq identified a small insertion, c.401_402insG (p.V134VfsX79), in PKD2. These methods do not overcome the screening complexity of homology. However, the true positives of variants confirmed by targeted gene and next-generation sequencing were 69.4%, 50% and 100% without a false positive in the whole coding region and the duplicated and unduplicated regions, which indicated that the screening accuracy of PKD1 and PKD2 can be largely improved by using a greater sequencing depth and elaborate design of the capture probe. [Copyright &y& Elsevier]

Abstract: Background: Cytokines have been implicated in the acute rejection of solid organ transplantation. Many studies have investigated the association between recipient or donor IL-4 polymorphism and acute rejection, with different studies reporting inconclusive results. Methods: We searched PUBMED and EMBASE until June 2012 to identify eligible studies investigating the association between IL-4 polymorphism with acute rejection after solid organ transplantation. Statistical analysis was performed using STATA10.0. Results: A total of 12 studies were included. Pooled ORs suggested 1) no significant association was detected between recipient or donor IL-4 −590C/T polymorphism and acute rejection of solid allograft; 2) no significant association was detected between recipient IL-4 −33C/T polymorphism and acute rejection of solid allograft; 3) when stratified by transplantation type, IL-4 −590C/T polymorphism was associated with acute rejection of liver transplantation (T/T+C/T vs. C/C: OR=0.36, 95%CI=0.14–0.90); 4) significantly decreased risk of acute rejection was detected in recipient IL-4 −590*T-negative/donor T-positive genotype pairs than all other recipient–donor IL-4 −590T/C pairs (OR=0.14, 95%CI=0.03–0.66). Conclusions: Our meta-analysis suggested that recipient IL-4 −590C/T polymorphism was associated with acute rejection of liver transplantation, but nor renal or heart transplantation. It was also suggested that combined recipient IL-4 −590*T-negative/donor T-positive genotype may suffer decreased risk of acute rejection of solid allograft. Further well-designed studies with larger sample size were required to verify our findings, with focus on the association of IL-4 polymorphism with acute rejection in patients with liver transplantation and studies investigating combined recipient–donor genotype. [Copyright &y& Elsevier]