PubMed Health⌕ Search

Biomedical subjects

D Coffman

Publications and source records attributed to D Coffman.

At least 19 recordsLinked to original sources
PubMed1994

Genetic linkage mapping for a susceptibility locus to bipolar illness: chromosomes 2, 3, 4, 7, 9, 10p, 11p, 22, and Xpter.

We are conducting a genome search for a predisposing locus to bipolar (manic-depressive) illness by genotyping 21 moderate-sized pedigrees. We report linkage data derived from screening marker loci on chromosomes 2, 3, 4, 7, 9, 10p, 11p, 22, and the pseudoautosomal region at Xpter. To analyze for linkage, two-point marker to illness lod scores were calculated under a dominant model with either 85% or 50% maximum penetrance and a recessive model with 85% maximum penetrance, and two affection status models. Under the dominant high penetrance model the cumulative lod scores in the pedigree series were less than -2 at theta = 0.01 in 134 of 142 loci examined, indicating that if the disease is genetically homogeneous linkage could be excluded in these marker regions. Similar results were obtained using the other genetic models. Heterogeneity analysis was conducted when indicated, but no evidence for linkage was found. In the course of mapping we found a positive total lod score greater than +3 at the D7S78 locus at theta = 0.01 under a dominant, 50% penetrance model. The lod scores for additional markers within the D7S78 region failed to support the initial finding, implying that this was a spurious positive. Analysis with affected pedigree member method for COL1A2 and D7S78 showed no significance for linkage but for PLANH1, at the weighting functions f(p) = 1 and f(p) = 1/sqrt(p) borderline P values of 0.036 and 0.047 were obtained. We also detected new polymorphisms at the mineralocorticoid receptor (MLR) and calmodulin II (CALMII) genes. These genes were genetically mapped and under affection status model 2 and a dominant, high penetrance mode of transmission the lod scores of < -2 at theta = 0.01 were found.

Bipolar Disorder↗
PubMed1994

Analysis of HLA DQ alpha allele and genotype frequencies in populations from Florida.

HLA DQ alpha allele and genotype frequencies for Caucasian, African American, Haitian, and Hispanic populations in Florida have been estimated. The Florida laboratories involved in these studies collected donor samples from a variety of sites including clinical laboratories, victim and suspect standards, blood banks, county jail detainees, and laboratory personnel. We have determined that the Caucasian and African American DQ alpha genotype frequencies do not deviate significantly from Hardy-Weinberg expectations and as a result of this heterogeneity analyses, data from the four Florida Caucasian populations may be combined and data from the four Florida African American populations may be combined to form two large HLA DQ alpha genotype frequency databanks. Further, data from the Florida Haitian population may be combined with the Florida African American population. Comparison of the combined Florida Caucasian populations, combined Florida African American populations, the Palm Beach Sheriff's Office (PBSO) Hispanic, and PBSO Haitian population with other databases does not support combination because allele frequency distributions are heterogeneous.

Alleles↗
PubMed1992

A systematic search for a bipolar predisposing locus on chromosome 5.

Chromosome 5 markers spanning the pter to the qter were used to examine linkage to bipolar illness in 14 pedigrees. Twenty-four loci were examined in 237 individuals, of whom 69 were either bipolars or schizoaffectives. Marker genotypes were determined for each individual and lod scores were calculated under a dominant disease model with a maximum penetrance of 85%, a disease gene frequency of 0.015, a variable age of onset, and a phenocopy rate of 0.001. Under the assumption that bipolar illness is genetically homogeneous, the total lod scores from all pedigrees with each marker were uniformly lower than -2.0, suggesting the absence of linkage to disease at any of these loci. Multipoint analysis allowed exclusion of intervals between markers. When lod scores were calculated allowing for heterogeneity, no subset of linked families was found. These results indicate that in our pedigree series almost the entire mapped region of chromosome 5 can be excluded for linkage to bipolar illness.

Bipolar Disorder↗