Bioinformatics Study of Spinocerebellar Ataxia Genes

10.30047/JGMB.200006.0008

Yuh-Fan Lin；Bing-Wen Soong；Ueng-Cheng Yang

Journal of Genetics and Molecular Biology

11卷2期（2000 / 06 / 01）

82 - 82

英文

The human genomics sequence draft has been completed. This draft covers about 90% of the human genome and the error rate is about 1%. Although draft sequence is fragmented, it is still useful for disease gene discovering. We have taken advantage of the characteristic sequence feature to discover the candidates for a trinucleotide repeat related diseases-Spinocerebellar Ataxia (SCA). An expansion of trinucleotide repeat had been shown to correlate with the severity of disease, which is observed in many neurological disorders, such as spinocerebellar ataxia, fragile X syndrome and Huntington’s disease. For those diseases that don’t have a candidate gene, a systematic search of human sequence database could provide candidates. Using the known SCA7 as an example, the location of the disease has been mapped to chromosome 3p14-p21.1 region. This region is roughly in between framework markers D3S1260 and D3S1261. All the markers between these two framework markers were collected and were used to detect high throughput genomic sequences (HTGS) in 3p14-p21.1 region. Seventy phase I sequences, two phase II sequences, and thirty phase III sequences were collected from a total of eighteen thousand or so HTGS. In these 102 sequences, only 12 of them have four or more CAG trinucleotide repeats. Two of these 12 sequences have trinucleotide repeats on the coding sequence. One of these two candidates is the known SCA7 gene. The same strategy has been applied to unknown SCA genes, such as type 4, 5, and 11. The possible candidates will be discussed.