ABP-280 is a ubiquitous actin binding protein present in the cytoskeleton of many different cell types. ABP-280 was mapped to distal Xq28, 50-60 kb downstream of the Green Colour Pigment (GCP) genes. To establish if ABP-280 may be a candidate for one of the muscle disease localized by linkage analysis to distal Xq28 we looked for alternative forms of ABP-280 mRNA. Several different ABP-280 mRNAs were indeed identified: two are X-linked and are produced by alternative splicing of a small exon of 24 nucleotides. At least one additional gene encoding a RNA more than 70% identical to ABP-280 in the 1700 bp sequenced has also been found. It was mapped to chromosome 7. While both forms of the X-linked ABP-280 are ubiquitous, the gene on chromosome 7 is highly expressed only in skeletal muscle and heart. The two genes were therefore excellent candidates for the X-linked and for the autosomal dominant form of the Emery-Dreifuss Muscular Dystrophy (EDMD) both of which have been described. So far, however we were unable to demonstrate mutations in the coding region or affecting the alternative splicing of the X-linked form of ABP-280, in several patients studied, and we think that it is quite unlikely that this is the gene responsible for EDMD.
DNA comprising 219 447 bp was sequenced in nine cosmids and verified at > 99.9% precision. Of the standard repetitive elements, 187 Alus make up 20.6% of the sequence, but there were only 27 MERs (2.9%) and 17 L1 fragments (1.6%). This may be characteristic of such high GC (57%) regions. The sequence also includes an 11.3 kb tract duplicated with 99.2% identity at a distance of 38 kb. The region is 80-90% transcribed and 12.5% translated. Thirteen known genes and their exon-intron borders are all accurately predicted at least in part by GRAIL programs, as are six additional genes. From centromere to telomere, the orientation of transcription varies among the first eight genes, then runs centromeric to telomeric for the next five, and is in the opposite sense for the last six. Eighteen of the 19 genes are associated with CpG islands. Two islands are exact copies in the 11.3 kb repeat units, and could thus give rise to double dosage levels of an X-linked gene. Another island is associated with two genes transcribed in opposite directions. From the sequence data, three genes and their exon structure are inferred. One of them, previously associated with HEX2, is shown to be a different gene unrelated to hexokinases; a second gene, previously known by an EST, is plexin, from its 65.5% identity with the Xenopus analog; and a third is a subunit of a vacuolar H-ATPase, and is named VATPS1.
A THEROSCLEROTIC LESIONS OF small coronary arteries are frequently found in patients undergoing revascularization. 1-5 However, the revascularization of small coronary arteries is a problem for bypass surgery because it is technically difficult and associated with a high failure and mortality rate 6,7 and for percutaneous coronary revascularization because it is associated with high rates of acute complications and restenosis after standard balloon angioplasty 1-3 and stent implantation. 4,5 It has been shown that sirolimuseluting stents reduce angiographic restenosis and improve the rate of eventfree survival in patients who have coronary artery disease and are at low risk of restenosis. 8 More recent reports For editorial comment see p 2777.
An increase in the number of (CAG)n repeats in the first coding exon of the androgen receptor (AR) gene has been strongly associated with Kennedy disease (KD) (spinal and bulbar muscular atrophy). This is an X-linked hereditary disorder characterized by motoneuron degeneration occurring in adults together with gynecomastia and hyperestrogenemia. We have performed AR gene molecular analysis in several members of a large family with KD as well as in 25 sporadic patients suffering from heterogeneous motoneuron disease (MND). An increase in the length of the (CAG)n repeats was detected, as expected, in all the affected males and in obligatory carrier females, some of which had minor signs of lower motoneuron involvement. There was only one possible exception, one young male with initial signs of the disease, who had an apparent normal length allele. An increased pathological allele was also found in 3 patients with MND. This indicates that the analysis of (CAG)n repeats of the AR gene plays a role in the differential diagnosis of this heterogeneous group of neurological diseases.
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.