Eumelanin and pheomelanin in tissue samples can be specifically measured as the markers pyrrole-2,3,5-tricarboxylic acid (PTCA) and 4-amino-3-hydroxyphenylalanine after acidic permanganate oxidation and hydroiodic acid hydrolysis, respectively. Those degradation methods, although widely applied, are not easily performed in most laboratories. To overcome this difficulty, we developed alkaline H(2)O(2) oxidation in 1 M K(2)CO(3) that produces, in addition to the eumelanin marker PTCA, thiazole-2,4,5-tricarboxylic acid (TTCA) and thiazole-4,5-dicarboxylic acid (TDCA) as markers for pheomelanin and pyrrole-2,3-dicarboxylic acid (PDCA) as a marker for 5,6-dihydroxyindole-derived eumelanin. Those four degradation products can be easily separated by HPLC and analyzed with ultraviolet detection. The alkaline H(2)O(2) oxidation method is simple, reproducible and applicable to all pigmented tissues. Its application to characterize eumelanin and pheomelanin in human hair shows that PTCA and TTCA serve as specific markers for eumelanin and pheomelanin, respectively, although some caution is needed regarding the artificial production of TTCA from eumelanic tissue proteins.
Age of myopia onset or duration of myopia progression was the most important predictor of high myopia in later childhood in myopic children. Future trials to retard the progression of myopia to high myopia could focus on children with younger age of myopia onset or with longer duration of myopia progression.
Genetic information in forensic studies is largely limited to CODIS data and the ability to match samples and assign them to an individual. However, there are circumstances, in which a given DNA sample does not match anyone in the CODIS database, and no other information about the donor is available. In this study, we determined 75 SNPs in 24 genes (previously implicated in human or animal pigmentation studies) for the analysis of single- and multi-locus associations with hair, skin, and eye color in 789 individuals of various ethnic backgrounds. Using multiple linear regression modeling, five SNPs in five genes were found to account for large proportions of pigmentation variation in hair, skin, and eyes in our across-population analyses. Thus, these models may be of predictive value to determine an individual’s pigmentation type from a forensic sample, independent of ethnic origin.
Microvillous Inclusion Disease (MID) is a rare, autosomal recessive gastrointestinal disease of increased frequency among the Navajos. Previous work has shown a deficiency of RAB8 in one Japanese patient, while homozygous mutations in MYO5B were found in 7 of 10 mostly Middle Eastern families. We have identified a shared homozygous mutation in MYO5B in seven affected Navajos with the expected heterozygosity in five parents. We have developed a simple restriction enzyme based assay that allows for rapid screening for this mutation.
of integration-free iPSCs from adult patients using the episomal vector approach. 10 Although significant effort has been made towards the derivation of iPSCs free of foreign DNA integration to avoid the disruption of host genome and potential reactivation of oncogenes used for reprogramming, these methods are generally much less efficient. 10 Our study demonstrates the feasibility of generating high quality integration-free iPSCs from adult patients. These established iPSC lines from schizophrenia patients with a defined DISC1 mutation will provide a useful resource for investigating the function of DISC1 in human neurodevelopment. Future studies using these iPSCs may serve as an entry point to clarify the molecular and cellular pathogenesis of schizophrenia.
Recently, genome-wide association studies (GWAS), meta-analyses, and replication studies focusing on bipolar disorder (BD) have implicated the α-1C subunit of the L-type voltage-dependent calcium channel (CACNA1C) and ankyrin 3 (ANK3) genes in BD. Based on the hypothesis that both schizophrenia (SZ) and BD may share some common genetic risk factors, we investigated the association of CACNA1C and ANK3 with SZ using meta-analytic techniques, combining all published data up to April 2015. Nine teams, including four European decent samples and five Asian samples, contributed 14,141 cases and 30,679 controls for the analysis of CACNA1C rs1006737 and SZ. A significant difference was identified between patients and controls for the A-allele of rs1006737 in combined studies (Z = 6.02, P = 1.74E-09), in European studies (Z = 4.08, P = 4.50E-05), and in Asian studies (Z = 4.60, P = 4.22E-06). Meanwhile, for the T-allele of ANK3 rs10761482 (1,794 cases versus 1,395 controls), a significant association was observed in combined samples (Z = 2.06, P = 0.04) and in Asian samples (Z = 3.10, P = 0.002). In summary, our study provides further evidence for the positive association of CACNA1C and ANK3 with SZ. These results support the hypothesis that both SZ and BD share common genetic risk factors. Further research is needed to examine the functions of CACNA1C and ANK3, and their interacting partners in the molecular, developmental, and pathophysiological processes in SZ.
MicroRNAs (miRNAs) are a class of endogenous and non-coding single-stranded RNAs of approximately 22 nucleotides, many of which are evolutionarily conserved. Genome-wide association studies have identified a robust statistical association between the MIR137 gene and schizophrenia in Europeans, which was replicated in the Han Chinese population in a case-control study. In the previous study, we provided evidence for a significant association between the EFNB2 gene and schizophrenia in Han Chinese subjects. In the current study, we utilized computational analysis, vector construction of point mutations, luciferase reporter assays and gene expression assays including RT-qPCR and western blotting methods to investigate miR-137 directly targeting EFNB2 gene and explore the reversal effect of a genetic variant of SNP rs550067317 in the putative seed-pair region of EFNB2 3′-UTR. We also found that miR-137 could be detected in the peripheral blood of a cohort of first-onset schizophrenia patients and healthy controls, and the area under curve was 0.795 (95% confidence interval 0.700–0.890), which is a middle diagnostic value for disease, suggesting that it might be valuable for diagnosing schizophrenia. In summary, this study would improve our understanding of the role of miR-137 in schizophrenia-associated signaling pathways and identify the genetic basis of rs550067317 for schizophrenia. Furthermore, we provided new evidence for the involvement of miR-137 in the etiology and diagnosis of schizophrenia, which might contribute to the discovery of new biomarkers and therapeutic targets for the disease.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.