On experiences of i2b2 (Informatics for integrating biology and the bedside) database with Japanese clinical patients' data.

Informatics for Integrating Biology and the Bedside (i2b2) is a database system to facilitate sharing and reuse of clinical patients' data collected in individual hospitals. The i2b2 provides an ontology based object-oriented database system with highly simple and flexible database schema which enables us to integrate clinical patients' data from different laboratories and different hospitals. 392 patients' data including carcinoma and non-carcinoma specimens from cancer patients are transported from the Integrated Clinical Omics Database (iCOD) to the i2b2 database for a feasibility study to check applicability of i2b2 ontology and database schema on Japanese clinical patients' data. No modification is required for the i2b2 data model to deal with Japanese characters. Some modification of ontology is required to integrate biomedical information extracted from the cancer patients' data. We believe that the i2b2 system will be practical infrastructure to integrate Japanese clinical databases if appropriate disease ontology for Japanese patients is provided.

Characterization of the complex 7q21.3 rearrangement in a patient with bilateral split-foot malformation and hearing loss.

We report on complex rearrangements of the 7q21.3 region in a female patient with bilateral split-foot malformation and hearing loss. G-banding karyotype was 46,XX,t(7;15)(q21;q15),t(9;14)(q21;q11.2)dn. By fluorescence, in situ hybridization (FISH), Southern hybridization, and inverse PCR, the 7q21.3 translocation breakpoint was determined at the nucleotide level. The breakpoint did not disrupt any genes, but was mapped to 38-kb telomeric to the DSS1 gene, and 258- and 272-kb centromeric to the DLX6 and DLX5 genes, respectively. It remains possible that the translocation would disrupt the interaction between these genes and their regulatory elements. Interestingly, microarray analysis also revealed an interstitial deletion close to (but not continuous to) the 7q21.3 breakpoint, indicating complex rearrangements within the split-hand/foot malformation 1 (SHFM1) locus in this patient. Furthermore, a 4.6-Mb deletion at 15q21.1-q21.2 adjacent to the 15q15 breakpoint was also identified. Cloning of the deletion junction at 7q21.3 revealed that the 0.8-Mb deletion was located 750-kb telomeric to the translocation breakpoint, encompassing TAC1, ASNS, OCM, and a part of LMTK2. Because TAC1, ASNS, and OCM genes were located on the reported copy number variation regions, it was less likely that the three genes were related to the split-foot malformation. LMTK2 appeared to be a potential candidate gene for SHFM1, but no LMTK2 mutations were found in 29 individuals with SHFM. Further LMTK2 analysis of SHFM patients together with hearing loss is warranted.

A novel epistatic interaction at two loci causing hybrid male sterility in an inter-subspecific cross of rice (Oryza sativa L.).

Postzygotic reproductive isolation (RI) often arises in inter-subspecific crosses as well as inter-specific crosses of rice (Oryza sativa L.). To further understand the genetic architecture of the postzygotic RI, we analyzed genes causing hybrid sterility and hybrid breakdown in a rice inter-subspecific cross. Here we report hybrid male sterility caused by epistatic interaction between two novel genes, S24 and S35, which were identified on rice chromosomes 5 and 1, respectively. Genetic analysis using near-isogenic lines (NILs) carrying IR24 (ssp. indica) segments with Asominori (ssp. japonica) genetic background revealed a complicated aspect of the epistasis. Allelic interaction at the S24 locus in the heterozygous plants caused abortion of male gametes carrying the Asominori allele (S24-as) independent of the S35 genotype. On the other hand, male gametes carrying the Asominori allele at the S35 locus (S35-as) showed abortion only when the IR24 allele at the S24 locus (S24-ir) was concurrently introgressed into the S35 heterozygous plants, indicating that the sterility phenotype due to S35 was dependent on the S24 genotype through negative epistasis between S24-ir and S35-as alleles. Due to the interaction between S24 and S35, self-pollination of the double heterozygous plants produced pollen-sterile progeny carrying the S24-ir/S24-ir S35-as/S35-ir genotype in addition to the S24 heterozygous plants. This result suggests that the S35 gene might function as a modifier of S24. This study presents strong evidence for the importance of epistatic interaction as a part of the genetic architecture of hybrid sterility in rice. In addition, it suggests that diverse systems have been developed as postzygotic RI mechanisms within the rice.

Mild craniosynostosis with 1p36.3 trisomy and 1p36.3 deletion syndrome caused by familial translocation t(Y;1).

We report on a 20-year-old man and a 16-year-old woman with a chromosomal imbalance derived from a balanced translocation, t(Y;1)(q12;p36.3) of the father. The man had a partial trisomy for 1p36.3-pter [46,X,der(Y)t(Y:1)(q12;p36.3)] and mild craniosynostosis of metopic and sagittal sutures as well as a borderline mental impairment, while the woman with a deletion for 1p36.3-pter [46,XX,der(1)t(Y;1)(q12;p36.3)] showed dysmorphic face with large anterior fontanel and severe developmental delay. Fluorescence in situ hybridization (FISH) showed that his trisomy spanned the 5.3-Mb region from 1p telomere harboring the critical region for craniosynostosis. To our knowledge, the man is the first case of a pure type of simple 1p36.3 trisomy as the effect of heterochromatic Yq12-qter deletion likely does not affect phenotype.