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A genome-wide scan for QTL affecting economically important traits in beef production was performed using an [F.sub.2] resource family from a Japanese Black x Limousin cross, where 186 [F.sub.2] animals were measured for growth, carcass, and meat-quality traits. All family members were genotyped for 313 informative microsatellite markers that spanned 2,382 cM of bovine autosomes. The centromeric region of BTA2 contained significant QTL (i.e., exceeding the genome-wide 5% threshold) for 5 carcass grading traits [LM area, beef marbling standards (BMS) number, luster, quality grade, and firmness), 8 computer image analysis (CIA) traits [LM lean area, ratio of fat area (RFA) to LM area, LM area, RFA to musculus (M.) trapezius area, M. trapezius lean area, M. semispinalis lean area, RFA to M. semispinalis area, and RFA to M. semispinalis capitis area], and 5 meat quality traits (contents of CP, crude fat, moisture, C16:1, and C18:2 of LM). A significant QTL for withers height was detected at 80.3 cM on BTA5. We detected significant QTL for the C14:0 content in backfat and C14:0 and C14:1 content in intermuscular fat around the 62.3 to 71.0 cM region on BTA19 and for C14:0, C14:1, C18:1, and C16:0 content and ratio of total unsaturated fatty acid content to total SFA content in intramuscular fat at 2 different regions on BTA19 (41.1 cM for C14:1 and 62.3 cM for the other 4 traits). Overall, we identified 9 significant QTL regions controlling 27 traits with genome-wide significance of 5%; of these, 22 traits exceeded the 1% genome-wide threshold. Some of the QTL affecting meat quality traits detected in this study might be the same QTL as previously reported. The QTL we identified need to be validated in commercial Japanese Black cattle populations. Key words: bovine, [F.sub.2] family, meat quality, quantitative trait loci

A genome-wide scan for QTL affecting economically important traits in beef production was performed using an F2 resource family from a Japanese Black × Limousin cross, where 186 F2 animals were measured for growth, carcass, and meat-quality traits. All family members were genotyped for 313 informative microsatellite markers that spanned 2,382 cM of bovine autosomes. The centromeric region of BTA2 contained significant QTL (i.e., exceeding the genomewide 5% threshold) for 5 carcass grading traits [LM area, beef marbling standards (BMS) number, luster, quality grade, and firmness), 8 computer image analysis (CIA) traits [LM lean area, ratio of fat area (RFA) to LM area, LM area, RFA to musculus (M.) trapezius area, M. trapezius lean area, M. semispinalis lean area, RFA to M. semispinalis area, and RFA to M. semispinalis capitis area], and 5 meat quality traits (contents of CP, crude fat, moisture, C16:1, and C18:2 of LM). A significant QTL for withers height was detected at 80.3 cM on BTA5. We detected significant QTL for the C 14:0 content in backfat and C14:0 and C 14:1 content in intermuscular fat around the 62.3 to 71.0 cM region on BTA19 and for C14:0, C14:1, C18:1, and C16:0 content and ratio of total unsaturated fatty acid content to total SFA content in intramuscular fat at 2 different regions on BTA19 (41.1 cM for C14:1 and 62.3 cM for the other 4 traits). Overall, we identified 9 significant QTL regions controlling 27 traits with genomewide significance of 5%; of these, 22 traits exceeded the 1% genome-wide threshold. Some of the QTL affecting meat quality traits detected in this study might be the same QTL as previously reported. The QTL we identified need to be validated in commercial Japanese Black cattle populations. [ABSTRACT FROM AUTHOR]

A 64-year-old man underwent kidney transplantation for progressive chronic renal failure which had developed 8 years after allogeneic bone marrow transplantation for acute myeloid leukemia. Because of post-operative complications, he had been placed on intravenous hyperalimentation. Three months after the transplantation, anemia rapidly progressed (hemoglobin, 7.9 g/dl). The proportion of reticulocytes was 0.2%, but white blood cell and platelet counts remained within normal ranges. Serum iron, vitamin B12, and folate levels were normal. Bone marrow examination showed the presence of ringed sideroblasts and cytoplasmic vacuoles in a fraction of erythroid cells. Megakaryocytes were adequate in number with normal morphology. Although the findings were consistent with refractory anemia with ringed sideroblasts according to the WHO classification, cytoplasmic vacuolations were also observed in myeloid cells, suggesting copper deficiency. Indeed, serum copper and ceruloplasmin levels were found to be low (33 μg/dl and 11 mg/dl, respectively), and oral copper supplementation at a daily dose of 1 mg was initiated. There was a prompt increase in reticulocytes, and the hemoglobin level was normalized within one month, in response to this regimen. In progressive anemia cases with ringed sideroblasts in the bone marrow, copper deficiency should be considered in the differential diagnosis.