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P R Boyd

Publications and source records attributed to P R Boyd.

9 recordsLinked to original sources
PubMed2002

Linkage disequilibrium mapping identifies a 390 kb region associated with CYP2D6 poor drug metabolising activity.

The cytochrome p450 enzyme, CYP2D6, metabolises approximately 20% of marketed drugs. CYP2D6 multiple variants are associated with altered enzyme activities. Genotyping 1018 Caucasians for CYP2D6 polymorphisms (G1846A, delT1707, delA2549 and A2935C), known to result in the recessive CYP2D6 poor drug metaboliser (PM) phenotype, identified 41 individuals with predicted PM phenotype. These 41 individuals were classified as 'cases'. Single nucleotide polymorphisms (SNPs) mapping within an 880 kb region flanking CYP2D6, were identified to evaluate potential association between genetic variation and the CYP2D6 PM phenotype. The 41 PM cases and 977 controls were genotyped and analysed for 27 SNPs. Associations were observed across a 390 kb region between 14 SNPs and the PM phenotype (P values from 6.20 x 10(-4) to 4.54 x 10(-35)). Haplotype analysis revealed more significant levels of association (P = 3.54 x 10(-56)). Strong (D' > 0.7) linkage disequilibrium (LD) between SNPs was observed across the same 390 kb region associated with the CYP2D6 phenotype. The observed phenotype:genotype association reached genome-wide levels of significance, and supports the strategy for potential application of LD mapping and whole genome association scans to pharmacogenetic studies.

Chromosome Mapping↗
PubMed2001

Single-nucleotide polymorphism alleles in the insulin receptor gene are associated with typical migraine.

We have identified a migraine locus on chromosome 19p13.3/2 using linkage and association analysis. We isolated 48 single-nucleotide polymorphisms within the locus, of which we genotyped 24 in a Caucasian population comprising 827 unrelated cases and 765 controls. Five single-nucleotide polymorphisms within the insulin receptor gene showed significant association with migraine. This association was independently replicated in a case-control population collected separately. We used experiments with insulin receptor RNA and protein to investigate functionality for the migraine-associated single-nucleotide polymorphisms. We suggest possible functions for the insulin receptor in migraine pathogenesis.

Alleles↗
PubMed2001

Migraine with aura susceptibility locus on chromosome 19p13 is distinct from the familial hemiplegic migraine locus.

Migraine is a common neurological disease with a major genetic component. Recently, it has been proposed that a single locus on chromosome 19p13 contributes to the genetic susceptibility of both rare familial hemiplegic migraine (FHM) and more common types of migraine, migraine with aura and migraine without aura. We analyzed 16 families for co-segregation of migraine with aura and chromosome 19p13 markers. Using multipoint model-free linkage analysis, we obtained a lod score of 4.28 near D19S592. Using an affecteds-only model of linkage, we observed a lod score of 4.79 near D19S592. We were able to provide statistical evidence that this locus on chromosome 19p13 is most likely not the gene CACNA1A, mutations in which cause FHM. These data indicate that chromosome 19p13 contains a locus which contributes to the genetic susceptibility of migraine with aura that is distinct from the FHM locus.

Base Sequence↗
PubMed1995

Subcutaneous dirofilariasis in Collier County, Florida, USA.

A 10-year review of the surgical pathology files of the Department of Pathology at Naples Community Hospital (Naples, FL, U.S.A.) revealed 10 cases of Dirofilaria tenuis and one of Dirofilaria ursi infection. The review consisted of only those lesions for which the pathologists had recorded the presence of a worm in the lesion. Therefore, an unknown number of subcutaneous lesions without parasites were not reviewed. Nine of the 11 cases of Dirofilaria were diagnosed as Dirofilaria or Dirofilaria tenuis originally. An additional case, previously diagnosed as Dirofilaria, was found to be a sparganum larva on review. This finding indicates that, because of the unfamiliarity of pathologists with the diagnostic characteristics of these nematode parasites, infections with Dirofilaria are underdiagnosed or misdiagnosed. If pathologists were more familiar with these parasites, their prevalence and the medical cost of this zoonosis in the southeastern United States could be determined more accurately.

Adult↗
PubMed1986

The inheritance of Felty's syndrome in a family with several affected members.

A family in which 3 siblings had Felty's syndrome is described. All affected family members shared the common haplotype HLA-A2, B15, Cw3 and DR4. In addition, all affected siblings possessed the A2 and ABO phenotype. Four unaffected siblings possessed either the HLA-A2, B15, Cw3 and DR4 haplotype or the A2 ABO phenotype or neither but not both. We believe our data support the hypothesis that multiple genetic factors are involved in the predisposition of family members to Felty's syndrome.

Adult↗
PubMed1977

Multiple hepatic adenomas and a hepatocellular carcinoma in a man on oral methyl testosterone for eleven years.

Numerous small hepatic adenomas and hepatocellular carcinoma developed in a man after 11 years of methyl testosterone ingestion. The man presented with an acute surgical abdomen and a large filling defect in the liver. Laparotomy disclosed hemoperitoneum and a large hepatic hematoma. Focal hemorrhagic infarction in the excised right liver lobe involved both adenomas and normal parenchyma. Review of the English literature reveals no other case of both a benign and a malignant hepatocellular neoplasm associated with anabolic steroid therapy. Hemorrhagic benign liver tumor must be considered in the differential diagnosis in both female and male patients on hormone therapy who present with acute abdominal pain.

Adult↗