Eleven single nucleotide polymorphisms and one triple nucleotide insertion of the human TGF-β III receptor gene

We found 11 single nucleotide polymorphisms and one triple nucleotide insertion in the cDNA of the human transforming growth factor β (TGF-β) III receptor gene (TGFBR3) located on 1p33–p32, encoding betaglycan, a component of the TGF-β receptor system. Inside the 5′ untranslated region (UTR), a G→A polymorphism was identified at position 311. In the open reading frame (ORF), a non-conservative T→C polymorphism was identified at position 392, and three conservative polymorphisms were found at positions 563 (G→A), 1548 (G→A), and 2370 (C→T). A triple nucleotide insertion (GCA) was identified at position 1419. Inside the 3′ UTR, six polymorphisms were identified: four G→A, at positions 2918, 3055, 3098, and 3355; one T→A, at position 3183; and one G→C, at position 3966. In addition to these changes, some divergences from the published sequence were observed in all 12 chromosomes tested. These included, in the ORF, an additional C after position 555, two additional G after position 563, and an additional T after position 1388. No T was found at position 1394. The alterations translate to a changed amino acid sequence. Inside the 3′ UTR, additional discrepancies were identified. The discovered changes and polymorphisms may be useful for further genetic studies of TGFBR3 receptor deficiencies. Received: December 22, 1999 / Accepted: February 25, 2000     

Localization of a gene for otosclerosis to chromosome 15q25-q26

Among white adults otosclerosis is the single most common cause of hearing impairment. Although the genetics of this disease are controversial, the majority of studies indicate autosomal dominant inheritance with reduced penetrance. We studied a large multi- generational family in which otosclerosis has been inherited in an autosomal dominant pattern. Five of16 affected persons have surgically confirmed otosclerosis; the remaining nine have a conductive hearing loss but have not undergone corrective surgery. To locate the disease- causing gene we completed genetic linkage analysis using short tandem repeat polymorphisms (STRPs) distributed over the entire genome. Multipoint linkage analysis showed that only one genomic region, on chromosome 15q, generated a lod score >2.0. Additional STRPs were typed in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis gene.      

Evaluation of the image quality of ink-jet printed paper copies of digital chest radiographs as compared with film: A receiver operating characteristic study

Paper copies of digital radiographs printed with the continuous ink-jet technique have proved to be of a high enough quality for demonstration purposes. We present a study on the image quality of ink-jet printed paper copies of digital chest radiographs, based on receiver operating characteristic (ROC) analysis. Eighty-three digital radiographs of a chest phatom with simulated tumors in the mediastinum and right lund, derived from a computed radiography (CR) system were presented in two series of hard copies as ink-jet printed paper copies and as laser recorded film. The images, with a matrix of 1,760×2,140 pixels, were printed with a spatial resolution of 10 pixels/mm in the CR film recorder as well as in the ink-jet printer. On film, every image was recorded in two versions, one optimized for the mediastinum and one for the lungs. On paper, only one image was printed; this constituted an effort to optimize both the mediastinum and the lungs. The ink-jet printed images, printed on a matt coated paper, were viewed as on-sight images with reflected light. The exdaminations were reviewed by six radiologists, and ROC curves were constructed. No significant difference was found between the performance of film and that of ink-jet paper prints. Because the cost for a paper copy is only a tenth of that of film, remarkable cost reductions can be achieved by using the ink jet technique instead. Our results show that further quality studies of ink-jet printed images are worthwhile.