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Dentatorubral and pallidoluysian atrophy (DRPLA) is an autosomal dominant neurodegenerative disorder characterized by combined systemic degeneration of the dentatofugal and pallidofugal pathways. We investigated a candidate gene and found that DRPLA patients had an expanded CAG trinucleotide repeat in a gene on the short arm of chromosome 12. The repeat size varied from 7-23 in normal individuals. In patients one allele was expanded to between 49-75 repeats or occasionally even more. Expansion was usually associated with paternal transmission and only occasionally with maternal transmission. Repeat size showed a close correlation with age of onset of symptoms and disease severity. We conclude that DRPLA is the seventh genetic disorder known to be associated with expansion of an unstable trinucleotide repeat.

Summary Different colors, such as purple, brown, red and white, occur in the pericarp of rice. Here, two genes affecting proanthocyanidin synthesis in red‐ and brown‐colored rice were elucidated. Genetic segregation analysis suggested that the Rd and A loci are identical, and both encode dihydroflavonol‐4‐reductase (DFR). The introduction of the DFR gene into an Rcrd mutant resulted in red‐colored rice, which was brown in the original mutant, demonstrating that the Rd locus encodes the DFR protein. Accumulation of proanthocyanidins was observed in the transformants by the introduction of the Rd gene into the rice Rcrd line. Protein blot analysis showed that the DFR gene was translated in seeds with alternative translation initiation. A search for the Rc gene, which encodes a transacting regulatory factor, was conducted using available DNA markers and the Rice Genome Automated Annotation System program. Three candidate genes were identified and cloned from a rice RcRd line and subsequently introduced into a rice rcrd line. Brown‐colored seeds were obtained from transgenic plants by the introduction of a gene containing the basic helix–loop–helix (bHLH) motif, demonstrating that the Rc gene encodes a bHLH protein. Comparison of the Rc locus among rice accessions showed that a 14‐bp deletion occurred only in the rc locus.

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Sixty-one patients who were diagnosed with mucosal gastric cancer have been successfully treated with two laparoscopic techniques at our institute from March 1992 to March 1997. One is laparoscopic wedge resection of the stomach using a lesion-lifting method for lesions of the anterior wall, the lesser curvature, and the greater curvature of the stomach. The other is laparoscopic intragastric mucosal resection for lesions of the posterior wall of the stomach and near the cardia or the pylorus. Indications are as follows: (1) preoperatively diagnosed mucosal cancer; (2) <25 mm diameter elevated lesions; and (3) <15 mm diameter depressed lesions without ulcer formation. Patients were discharged in 4 to 8 days uneventfully. There was no major complication or mortality. The resected specimens had sufficient surgical margins horizontally (16 +/- 5 and 8 +/- 4 mm, respectively) and vertically. In one patient histologic examination revealed slight tumor infiltration into the submucosal layer with lymphatic invasion. He underwent gastrectomy with lymph node dissection 1 month after surgery. Otherwise, histologic examination revealed curative surgery. All patients in the series have survived during the 4- to 65-month follow-up period. There have been two recurrences in the series, both of which were found near the staple line 2 years after the initial surgery and were still mucosal lesions. They were successfully treated by open gastrectomy and laser irradiation. A separate early gastric cancer was found 2 years after the initial surgery in one patient, who then underwent curative open gastrectomy. In conclusion, if the patients are selected properly, these laparoscopic procedures are curative, minimally invasive treatment for early gastric cancer.

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Phenotypic measurements of chicken egg character and production traits are restricted to mature females only. Marker assisted selection of immature chickens using quantitative trait loci (QTL) has the potential to accelerate the genetic improvement of these traits in the chicken population. The QTL for 12 traits (i.e. body weight (BW), six for egg character, three for egg shell colour and two for egg production) of chickens were identified. An F2 population comprising 265 female chickens obtained by crossing White Leghorn and Rhode Island Red breeds and genotyped for 123 microsatellite markers was used for detecting QTL. Ninety-six markers were mapped on 25 autosomal linkage groups, and 13 markers were mapped on one Z chromosomal linkage group. Eight previous unmapped markers were assigned to their respective chromosomes in this study. Significant QTL were detected for BW on chromosomes 4 and 27, egg weight on chromosome 4, the short length of egg on chromosome 4, and redness of egg shell colour (using the L*a*b* colour system) on chromosome 11. A significant QTL on the Z chromosome was linked with age at first egg. Significant QTL could account for 6-19% of the phenotypic variance in the F2 population.

In order to locate the genetic regions in the swine genome that are responsible for economically important traits, a resource population has been constructed by mating two female Meishan pigs with a male Göttingen miniature pig. In subsequent generations, 265 F2 offspring were produced from two F1 males and 19 F1 females. The F2 offspring were scored for eight traits including growth rate, teat number, vertebra number and backfat thickness, and genotyped for 318 genetic markers spanning the swine genome. Least-square analysis revealed quantitative trait loci (QTL) effects for vertebra number on chromosomes 1 and 2; for teat number on chromosomes 1 and 7; for birth weight on chromosome 1; for average daily gain between 4 and 13 weeks of age on chromosomes 9 and 10; for backfat thickness on chromosome 7; and for backskin thickness on chromosome 3.