Biomedical subjects

Chitoshi Orimoto

Publications and source records attributed to Chitoshi Orimoto.

4 recordsLinked to original sources

PubMed2005

DNA polymorphisms and haplotypes in the 5'-upstream region of the ABO blood group gene.

We investigated the polymorphisms in the 5'-upstream region between nucleotide position (nt) -9600 and nt-4105 of the ABO blood group gene using PCR and direct sequencing methods. We found 16 single nucleotide polymorphisms, two insertion-deletion polymorphisms and two sequence polymorphisms. One of the insertion-deletion polymorphisms was found at nts from -9605 to -9204, and the alleles of that locus were named ABORR*L (non-deletion) and ABORR*S (52-base-deletion). There were two haplotypes constructed from 14 polymorphisms in the region between nt-9600 and nt-7565; they were tentatively named ABORR*L-associated and ABORR*S-associated haplotypes. The ABORR*L-associated haplotype may link with ABO*O(A) (also known as ABO*O201), and the ABORR*S-associated haplotype links with the other common alleles. This indicates the existence of two major lineages of the Japanese ABO alleles in the 5'-upstream region from nt-7565. In contrast to these findings, we observed six haplotypes in the region between nt-6371 and nt-4105, and we assume that the sequence in that region is variable as compared with those in the other 5'-upstream regions. We examined the generation of two sequence polymorphisms found in the present study. In the both cases, the formation of a hairpin loop caused by palindrome in a single-stranded DNA molecule may play an important role in generating the polymorphism.

5' Flanking Region↗

PubMed2003

Single nucleotide polymorphisms in the human complement C6 and C7 genes.

We analyzed the single nucleotide polymorphisms (SNPs) in the sixth (C6) and the seventh (C7) component genes of the complement system in a sample of the Japanese population, using polymerase chain reaction (PCR)-based methods and PCR direct sequencing. SNPs in the C6 gene studied here are as follows: A413C in exon 3, T1674C in exon 10, T7145A in exon 13, G[357+32]A in intron 2, and G[503-78]A in intron 3. We confirmed that nt413A and nt413C were associated with C6A and C6B, respectively. The result of the nt2145 typing showed that two subtypes exist in the C6B allotype. The SNP of G[357+32]A in intron 2 could be analyzed by using the PCR-RFLP method with HinfI. Allele frequencies in the Japanese population were found to be *G=0.920 and *A=0.080. SNPs in the C7 gene are as follows: T382C in exon 4, G1166C and A1258C in exon 9, and G[+10]A in intron 13. Nt382C and nt1258C would be responsible for C7-5 (=C7-3) and C7-4 allotypes, respectively.

Complement C6↗

PubMed2003

Short tandem repeat typing in exon 1 of the androgen receptor gene.

Exon 1 of the androgen receptor (AR) gene on the X chromosome contains a polymorphic CAG trinucleotide short tandem repeat. We describe here the rapid and reliable method of typing CAG repeats using electrophoresis, with denaturing polyacrylamide gel and an allelic ladder marker. Twenty-one alleles (the repeat number ranges from 13 to 35) were found using CAG repeat typing in normal Japanese individuals (83 males and 82 females). The allelic diversity (h) calculated was h=0.889, illustrating that CAG repeats at the AR locus is a highly polymorphic system.

Chromosomes, Human, X↗

PubMed2003

A-elute alleles of the ABO blood group system in Japanese.

The ABO blood group system is important in forensic genetics, as well as transfusion medicine. Since the elucidation of the molecular basis of ABO gene regulation, nucleotides of variant alleles or suballeles have been analyzed by polymerase chain reaction (PCR)-based methods and sequencing. Ael (A-elute) is one of the subgroups of A in the ABO system. By analyzing the suballeles responsible for Ael phenotype by PCR-RFLP and PCR direct sequencing, we found seven types of Ael allele. The allele frequency of ABO*Ael in a Japanese population was calculated to be 0.0049.

ABO Blood-Group System↗