PubMed:12424189
Annnotations
{"target":"https://pubannotation.org/docs/sourcedb/PubMed/sourceid/12424189","sourcedb":"PubMed","sourceid":"12424189","source_url":"http://www.ncbi.nlm.nih.gov/pubmed/12424189","text":"The molecular genetics of the human I locus and molecular background explain the partial association of the adult i phenotype with congenital cataracts.\nThe human i and I antigens are characterized as linear and branched repeats of N-acetyllactosamine, respectively. Conversion of the i to the I structure requires I-branching beta-1,6-N-acetylglucosaminyltransferase activity. It has been noted that the null phenotype of I, the adult i phenotype, is associated with congenital cataracts in Asians. Previously, the identification of molecular changes in the IGnT gene, associated with the adult i phenotype, has been reported. In the present study, we demonstrate that the human I locus expresses 3 IGnT forms, designated IGnTA, IGnTB, and IGnTC, which have different exon 1, but identical exons 2 and 3, coding regions. The molecular genetics proposed for the I locus offer a new perspective on the formation and expression of the I antigen in different cells and provide insight into the questions derived from investigation of the adult i phenotype. Molecular genetic analyses of the I loci of the 2 adult i groups, with and without congenital cataracts, were performed, and enzyme function assays and expression patterns for the 3 IGnT transcripts in reticulocytes and lens-epithelium cells were analyzed. The results suggest a molecular genetic mechanism that may explain the partial association of the adult i phenotype with congenital cataracts and indicate that a defect in the I locus may lead directly to the development of congenital cataracts. The results also suggest that the human blood group I gene should be reassigned to the IGnTC form, not the IGnTB form, as described previously.","tracks":[{"project":"GGDB-2020","denotations":[{"id":"T1","span":{"begin":559,"end":563},"obj":"https://acgg.asia/db/ggdb/info/gg111"},{"id":"T2","span":{"begin":700,"end":704},"obj":"https://acgg.asia/db/ggdb/info/gg111"},{"id":"T3","span":{"begin":1236,"end":1240},"obj":"https://acgg.asia/db/ggdb/info/gg111"}],"attributes":[{"subj":"T1","pred":"source","obj":"GGDB-2020"},{"subj":"T2","pred":"source","obj":"GGDB-2020"},{"subj":"T3","pred":"source","obj":"GGDB-2020"}]},{"project":"ggdb-test","denotations":[{"id":"T1","span":{"begin":559,"end":563},"obj":"https://acgg.asia/db/ggdb/info/gg111"},{"id":"T2","span":{"begin":700,"end":704},"obj":"https://acgg.asia/db/ggdb/info/gg111"},{"id":"T3","span":{"begin":1236,"end":1240},"obj":"https://acgg.asia/db/ggdb/info/gg111"}],"attributes":[{"subj":"T1","pred":"source","obj":"ggdb-test"},{"subj":"T2","pred":"source","obj":"ggdb-test"},{"subj":"T3","pred":"source","obj":"ggdb-test"}]},{"project":"glycogenes","denotations":[{"id":"PD-GlycoGenes20190927-B_T1","span":{"begin":381,"end":384},"obj":"https://acgg.asia/db/ggdb/info/gg135"},{"id":"PD-GlycoGenes20190927-B_T2","span":{"begin":559,"end":563},"obj":"https://acgg.asia/db/ggdb/info/gg111"},{"id":"PD-GlycoGenes20190927-B_T3","span":{"begin":609,"end":612},"obj":"https://acgg.asia/db/ggdb/info/gg135"},{"id":"PD-GlycoGenes20190927-B_T4","span":{"begin":700,"end":704},"obj":"https://acgg.asia/db/ggdb/info/gg111"},{"id":"PD-GlycoGenes20190927-B_T5","span":{"begin":712,"end":722},"obj":"url"},{"id":"PD-GlycoGenes20190927-B_T6","span":{"begin":1236,"end":1240},"obj":"https://acgg.asia/db/ggdb/info/gg111"}],"attributes":[{"subj":"PD-GlycoGenes20190927-B_T1","pred":"source","obj":"glycogenes"},{"subj":"PD-GlycoGenes20190927-B_T2","pred":"source","obj":"glycogenes"},{"subj":"PD-GlycoGenes20190927-B_T3","pred":"source","obj":"glycogenes"},{"subj":"PD-GlycoGenes20190927-B_T4","pred":"source","obj":"glycogenes"},{"subj":"PD-GlycoGenes20190927-B_T5","pred":"source","obj":"glycogenes"},{"subj":"PD-GlycoGenes20190927-B_T6","pred":"source","obj":"glycogenes"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"GGDB-2020","color":"#ecb493","default":true},{"id":"ggdb-test","color":"#9a93ec"},{"id":"glycogenes","color":"#a6ec93"}]}]}}