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Hereditary pancreatitis (HP) is an autosomal dominant disorder with incomplete penetrance characterized by recurring episodes of severe abdominal pain often presenting in childhood. Although this disorder has only been recently described, about 100 families have been documented worldwide. The pathophysiology of this disorder is unknown. Here, a large French family of 147 individuals (47 of whom were affected) from a four-generation kindred with HP has been examined and a genome segregation analysis of highly informative microsatellite markers has been performed. Linkage has been found between HP and six chromosome 7q markers. Maximal two point lod scores between HP and D7S 640, D7S 495, D7S 684, D7S 661, D7S 676 and D7S 688 were 4.00 (theta = 0.143), 5.85 (theta = 0.143), 4.91 (theta = 0.156), 8.58 (theta = 0.077), 8.28 (theta = 0.060), 4.40 (theta = 0.169), respectively. Multipoint linkage data combined with recombinant haplotype analysis indicated that the most likely order is: D7S 640-D7S 495-D7S 684-D7S 661-D7S 676-D7S 688, with the HP gene situated in the underlined region. As in all families reported in the literature, the clinical presentation of the disease is identical to the presentation of sporadic cases, one could expect that the knowledge of the HP gene could be a clue to pancreatitis in general. Based on its map position, this is the first step towards the positional cloning of the Hereditary Pancreatitis Gene (HPG).

This paper describes a genetic algorithm that deals with the assembly plaizning problem. While iiiost usseriibly plaiiniiig systeiiis use a cut-set iiiethod to generate usseiiibly plans, we propose a new approach to this problem: we use a genetic algorithm that generates and evaluates asseinbly plans. This algorithm starts from a set of valid assenibly plans proposed by an expert of the product. This set is the iiiitinl popirlutiori of poteiitiril solutions. Each asseinbly plan is eiicoded into a chronimonie, to be iiianipulatecl by genetic operators. A reproduction process uses these operntors to prodiice new asseinbly plciiis fi-om "parents" assembly plans. An evalirntioii jiiiiction nricl a selection procedure retniii the best plans that expmid the popirlatioii and sene for new generations. This algorithrii can be used either to quickly generate a set of good assembly plans, or to search all the valid assembly yluiis of a procliict.

No abstract

Major histocompatibility complex (MHC) class II antigens are discordantly expressed on hematopoietic progenitor cells. Their expression is linked to differential responsiveness of the cells to growth factors and inhibitors. We examined the expression of different MHC class II antigens in a panel of human myelomonocytic cell lines representing different stages of differentiation, by cytofluorographic analysis with monoclonal antibody (MoAb) and Northern blot analysis with specific cDNA probes. These analyses revealed discordant expression of different MHC class II antigens both in basal state and after gamma-IFN induction. Thus KG-1 myeloblast cells express all class II antigens (DR greater than DP greater than DQ) constitutively and their expression increased after gamma-IFN treatment. KG-1a, an immature blast variant of KG-1, does not express class II antigens, even after gamma-IFN treatment. THP-1, a monocytic cell line expresses DR but not DP or DQ under basal conditions. DP and DQ are, however, gamma-IFN inducible. The class II negative HL-60 promyelocytic cell line, expresses DR and DP but not DQ after gamma-IFN induction. In all the above cell lines, surface expression of class II antigens correlated with the levels of mRNA expression as determined with specific cDNA probes. In U-937, a monocytic cell line, no surface expression of class II MHC antigens was observed either with or without gamma-IFN, however, specific mRNA message was observed under basal conditions and was further increased with gamma-IFN, indicating a possible defect in assembly or transport of class II antigens. The patterns of class II MHC antigens in these leukemic cell lines may be a useful model to delineate molecular basis of discordant MHC class II expression during myelomonocytic differentiation.

This paper describes a method for the generation of assembly sequences with ternary operations. While most assembly sequences planners dear1 with sequences where the operations mate two parts, we propose a methlod that generate sequences with ternary operations, that assemble simultaneously three parts. This method examines first the situations where a ternary operation is more efficient than two binary operations. Then it determines the irernary operations that are missed by the assembly sequences planners with binary operations. This methoa! is an extension of the traditional assembly sequences planners where the combinatorial explosion of such prob1e)ms can still be handled.

J. D. Bignon, M. L. Cheneau, P. Herry, F. Bonneville, A. Cesbron, J. Y. Muller. Strong linkage disequilibrium of HLA DPw11 with the HLA B44‐DR7‐DQw2 extended haplotype. Tissue Antigens 1992: 39: 35‐37.

No abstract