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D Stauffer

Publications and source records attributed to D Stauffer.

At least 37 records · Page 2Linked to original sources
PubMed1995

Physical and genetic localization of a Shab subfamily potassium channel (KCNB1) gene to chromosomal region 20q13.2.

A human delayed rectifier K+ channel gene has been localized to the long arm of human chromosome 20q13.2 by fluorescence in situ hybridization of genomic P1 clones from this locus. A polymorphic (GA) microsatellite repeat was identified in one of the P1 clones. The new SSR marker (D20S436) was genotyped in four CEPH pedigrees. Two-point linkage analysis indicated linkage of this marker to a PCR marker, D20S109, with a maximum lod score of 9.32 at theta = 0.001. The assignment of this K+ channel gene to 20q13.2 eliminates it as a candidate for the gene associated with benign familial neonatal convulsions (BFNC), which has been localized to 20q13.3. Genetically, the K+ channel gene maps more than 30 cM proximal to the BFNC locus.

Base Sequence↗
PubMed1995

Genetic mapping of adrenergic receptor genes in humans.

We have genetically mapped the genes encoding four human adrenergic receptors (ARs) of subtypes alpha 1C, alpha 2A, alpha 2B, and beta 1, which are prototypic G protein coupled receptors that mediate the physiological effects of neurotransmitters, hormones, and drugs. We placed these genes onto the Cooperative Human Linkage Center (CHLC) and Genethon framework maps, within confidence intervals with greater than 1000:1 odds. With multipoint analysis the alpha 1C gene (locus ADRA1C) mapped to the interval between NEFL and D8S283; alpha 2-C4, the gene encoding the alpha 2C AR (locus ADRA2C), mapped to the interval between D4S126 and D4S62; and the alpha 2-C10 (alpha 2A AR)/beta 1 haplotype (loci ADRA2A/ADRB1) mapped to the interval between D10S259 and D10S187. A fifth AR gene, beta 2, yielded significant LOD scores with markers on the long arm of chromosome 5; however, this locus (ADRB2) could not be mapped to any specific interval with odds of greater than 1000:1. The two AR genes that are completely linked, alpha 2-C10 and beta 1, were oriented on their shared 225-kb genomic fragment relative to the direction of transcription, with beta 1 being 5' to alpha 2-C10. The positioning of these genes on high-density framework maps allows them to be tested as candidates in a spectrum of diseases that might involve AR dysfunction.

Base Sequence↗
PubMed1994

Size effects in Kauffman type evolution for rugged fitness landscapes.

Millions of sites are simulated in an NK fitness model of evolution and coevolution. We find a logarithmic size dependence of the number of hill-climbing iterations needed to reach a local fitness optimum (Nash equilibrium). We also check for chaotic behavior and determine the size of the damage clouds or avalanches. Random noise (simulated annealing) is shown to increase appreciably the fitness.

Algorithms↗
PubMed1994

High-dimensional simulation of simple immunological models.

We propose a simple model for idiotypic-antiidiotypic immunological networks which represents a simplification of the model originally suggested by Stewart & Varela, and de Boer, van der Laan & Hogeweg. Window cellular automata enlarge the antibody concentration if the influence of the immediate neighborhood lies between 70 and 99% of its maximum value; in addition random recruitment is possible. We simulate the model on large square lattices as well as in higher dimensions. The results are in qualitative agreement with those of the earlier model. Moreover, in five to ten dimensions we find phase separation for not too large recruitment, which then leads to domains growing to "infinity" for infinite times.

Animals↗
PubMed1993

A genetic linkage map with 29 loci spanning human chromosome 13q.

A genetic linkage map for the long arm of human chromosome 13 contains 29 loci derived from 38 probe and enzyme combinations and two protein polymorphisms. Thirteen loci form a continuous linkage map of 106 cM in males and 230 cM in females; each was placed on the map with support of at least 1000:1 against alternative orders. On a sex-combined basis, the mean distance between markers is less than 13 cM. The order of loci on the genetic map agrees with physical localization data that show that together these 13 loci cover 13q13 to 13q34. This map was used to regionally localize the 16 remaining loci. The linkage maps reported here should prove to be useful to investigators mapping disease genes and other genetic markers on human chromosome 13.

Alleles↗
PubMed1992

Genetic linkage of the human gene for phenylethanolamine N-methyltransferase (PNMT), the adrenaline-synthesizing enzyme, to DNA markers on chromosome 17q21-q22.

We have determined the genetic location of the human gene encoding phenylethanolamine N-methyltransferase (PNMT), the terminal enzyme of the catecholamine pathway catalyzing the synthesis of epinephrine (adrenaline) from norepinephrine. This gene is linked to DNA markers on the long arm of chromosome 17, q21-q22, most closely to the DNA markers MFD15 (D17S250) (Zmax = 15.0, theta = 0.065) and fLB17.1 (Zmax = 14.6, theta = 0.045). Multipoint linkage analysis placed the PNMT locus in the interval fLB17.1-CMM86 (D17S74), at 4 centiMorgans (cM) distal to fLB17.1, and at 17 cM proximal to CMM86. Mapping of the PNMT gene will provide the basis for genetic linkage studies in families with disease which might pathogenetically involve this enzyme. The human chromosomal region 17q21-22 identified here to harbour the PNMT gene may be syntenic to the chromosomal region in the stroke-prone spontaneously hypertensive rat (SHR-SP) recently linked to blood-pressure regulation. As an increase of PNMT activity has been associated with the development of hypertension in SHR-SP, it will be of interest to perform comparative mapping of the PNMT gene.

Animals↗
PubMed1992

Linkage of a variant or attenuated form of adenomatous polyposis coli to the adenomatous polyposis coli (APC) locus.

Adenomatous polyps are an intermediate in the pathway to colon carcinoma. An inherited disorder, familial adenomatous polyposis coli (APC), is characterized by hundreds to thousands of adenomatous polyps. A previously reported family had colon cancer associated with a low average but highly heterogenous number of colonic polyps, this phenotype mapped to the APC locus on 5q. Four new families have been ascertained in which the phenotypic pattern was different from classical polyposis but similar to that of the "prototype" kindred reported earlier. By multilocus linkage analysis, the gene responsible for the disease phenotype was mapped, with a high level of confidence, to the APC locus in two of the four families with the attenuated or variant form of polyposis (AAPC); the results for the two remaining kindreds were inconclusive. A combined maximum LOD score of approximately 7.6 at a recombination fraction of 0 was obtained when the results were summed over the four pedigrees with markers closest to the APC locus. The establishment of genetic linkage in such families may point to the APC locus as having a more significant role in inherited predispositions to colorectal cancer than was previously thought.

Adenomatous Polyposis Coli↗
PubMed1991

A discrete model for immune surveillance, tumor immunity and cancer.

In this paper we propose a model of tumor immunity in terms of discrete automata where each automation describes the concentration of one particular type of cell involved in immune response. In contrast to the earlier models of normal immune response, there is more than one type of cell surface antigen in this model. As a consequence, the tumor can evade destruction through humoral response by changing its identity. However, the tumor can be killed by the killer cells through cell-mediated response unless protected by a high concentration of the suppressor T cells.

Computer Simulation↗
PubMed1991

Discordance of T-cell receptor beta-chain genes in familial multiple sclerosis.

Restriction fragment length polymorphisms of the T-cell receptor beta-chain gene were studied in DNA obtained from 96 individuals from 14 multiplex families with multiple sclerosis (MS). Thirty-four family members had definite MS and two had probable MS. Five normal family members had abnormal findings on cranial magnetic resonance imaging (MRI) scans. Linkage analysis was performed using the BglII and the KpnI polymorphisms. With penetrance values from 0.1 to 0.7, and altering the scoring of the normal individuals with abnormal findings on MRI scans from "unknown" to "affected," log of the odds scores between -4.59 to -12.76 were found for the autosomal dominant model. For the autosomal recessive model with a penetrance range from 0.1 to 1.0, the LOD scores ranged from -8.20 to -32.98. These findings do not support a direct role of T-cell receptor beta-chain gene in the inheritance of MS.

Alleles↗