L. Anderson

UDP glucuronosyltransferases (UGTs) comprise a multigene family of drug-metabolizing enzymes. The sub-family of UGTs that conjugate bilirubin and phenolic compounds with glucuronic acid has been termed UGT1A1. In man, UGT1A1 isoforms are encoded by a single gene, UGT1A1. Protein isoforms encoded by UGT1A1 originate by alternative splicing. In the present study, we used the cDNA of UGT1A1*4, a bilirubin-conjugating isoform, to localize the UGT1A1 locus in the human genome. The UGT1A1 gene was assigned by in situ hybridization to chromosome region 2q37.

For most observers, Iraq's recent elections were an important first step on the road to democratic normalcy. However, three related outcomes—the political marginalization of Sunni Arabs, the electoral gains made by Shi'a religious parties, and the triumphant performance of the Kurds—render the task of crafting Iraq's permanent constitution significantly more problematic. In this paper, we examine the implications of these election results for the design of Iraq's federal system. Our focus is on the character of the subunits in any future system, specifically on whether Iraq should adopt a form of territorial federalism based on the country's existing eighteen provinces (as most scholars argue) or whether a form of ethnic, or “plurinational,” federalism based on five regions would be better able to address the very significant problems created by the election results. After assessing the relative merits of the various proposals for a federal Iraq, we conclude that a system based on five broad regions, though not ideal, is the least bad of the options available.

Conventional fixation for thin-section microscopy is insufficient to preserve many elements of cells and tissues. Actin filaments, for example, are destroyed during post-fixation in OsO4. In our search for a better fixative, we chose pellets of pure actin filaments as a very sensitive model system. In the present study, the potential of amines for improving aldehyde fixation was explored, and the results were compared to those obtained with the use of tannic acid. Aldehyde and amine were used together as an initial fixative, followed by aldehyde alone with postfixation in 1% OsO4 in buffer at 4 degrees C for 15 min, uranyl acetate en bloc stain, acetone dehydration, and embedding in Epox 812. Some primary monoamines improved the preservation of filaments; filaments were not broken beyond recognition by OsO4, as occurs when glutaraldehyde alone is used. Excellent preservation was seen when certain primary diamines were used. The quality of this fixation was superior to that obtained with tannic acid and was without the large increase in filament diameter that is seen with concentrations of tannic acid sufficient to protect filaments against osmium damage. The effects on filaments of the amines lysine, putrescine, ammonium, and arginine have been documented in detail, as we systematically varied all the major parameters normally considered in formulating fixation protocols.

Multiple endocrine neoplasia type 2A (MEN2A) is a rare cancer syndrome that is inherited in an apparently autosomal dominant fashion. Previous linkage studies had assigned the MEN2A locus to chromosome 10 in the pericentromeric region. We recently have described several new easily scorable RFLPs for the chromosome 10-specific alpha satellite DNA (the D10Z1) locus that is known, on the basis of previous in situ hybridization experiments, to lie at the centromere. We report here tight linkage between MEN2A and D10Z1, as demonstrated by a maximum lod score of 12.02 at the recombination frequency of zero (1-lod-unit support interval 0-4 cM), indicating that the genetic defect in MEN2A lies in the immediate vicinity of the centromere. By means of a set of ordered polymorphic DNA markers from the pericentromeric region, multipoint as well as pairwise linkage analyses place the MEN2A locus at the middle of a small region (approximately 11 cM) bracketing the centromere with FNRB (at 10p11.2) and RBP3 (at 10q11.2) on either side, providing further support for the centromeric location of the MEN2A locus. Marked sex difference in recombination frequencies exists in this pericentromeric region: significantly (P less than .01) more female than male crossovers were observed across all of the adjacent intervals D10S24-FNRB, FNRB-D10Z1, and D10Z1-RBP3. However, a sex difference was not seen in the 7-cM interval from RBP3 to D10S5, suggesting that large variation in the sex difference in recombination can occur over small chromosomal regions.(ABSTRACT TRUNCATED AT 250 WORDS)