A sequence-based variation map of 8.27 million SNPs in inbred mouse strains.

A dense map of genetic variation in the laboratory mouse genome will provide insights into the evolutionary history of the species and lead to an improved understanding of the relationship between inter-strain genotypic and phenotypic differences. Here we resequence the genomes of four wild-derived and eleven classical strains. We identify 8.27 million high-quality single nucleotide polymorphisms (SNPs) densely distributed across the genome, and determine the locations of the high (divergent subspecies ancestry) and low (common subspecies ancestry) SNP-rate intervals for every pairwise combination of classical strains. Using these data, we generate a genome-wide haplotype map containing 40,898 segments, each with an average of three distinct ancestral haplotypes. For the haplotypes in the classical strains that are unequivocally assigned ancestry, the genetic contributions of the Mus musculus subspecies--M. m. domesticus, M. m. musculus, M. m. castaneus and the hybrid M. m. molossinus--are 68%, 6%, 3% and 10%, respectively; the remaining 13% of haplotypes are of unknown ancestral origin. The considerable regional redundancy of the SNP data will facilitate imputation of the majority of these genotypes in less-densely typed classical inbred strains to provide a complete view of variation in additional strains.

Prevalence of hyperprolactinemia in schizophrenia: association with typical and atypical antipsychotic treatment.

OBJECTIVE: To evaluate the prevalence and severity of hyperprolactinemia among a large sample of patients with schizophrenia and related psychotic disorders treated with typical and atypical antipsychotic medications. METHOD: Three electronic databases (general medical, psychiatric, and pharmacologic) containing the census data from November 2002 through March 2003 for a state-funded, inpatient hospital serving the chronically mentally ill were merged (N = 470). This database was purged of patient names, while the unique hospital identification number and demographic variables in each record were retained. These records were then screened to exclude patients with medications (except neuroleptics) or medical conditions known to elevate or suppress prolactin, leaving an overall sample (N = 422) in which to evaluate the prevalence of hyperprolactinemia. The sample was composed of patients with DSM-IV schizophrenia (N = 213), other related psychotic disorders (N = 131), mood disorders (N = 44), and other disorders (N = 34). RESULTS: For the overall sample (N = 422), which combined men and women, the mean serum prolactin level was 41.5 ng/mL; 290 of 422 patients were above the normal range. For women (N = 133), the mean serum prolactin level was 57.9 ng/mL, and 67% had levels above normal. For men (N = 289), the mean level was 33.9 ng/mL, with a 70% prevalence of hyperprolactinemia. While age did not influence the prevalence of elevated prolactin among men, age (reflecting reproductive status) was a significant variable in women; older age was associated with lower prolactin levels. For the study sample, a highly significant correlation was observed between neuroleptic dose (chlorpromazine equivalent) and serum prolactin level; however, this relationship was not determined on a medication-by-medication basis. Medications known to elevate prolactin were associated with higher prevalence rates of hyperprolactinemia, and "prolactin-sparing" medications had lower prevalence rates. However, when they were used in combination, the prolactin-elevating medication overwhelmed the effects of prolactin-sparing medication. CONCLUSIONS: This study suggested that neuroleptic treatment of schizophrenia is strongly associated with hyperprolactinemia and showed important differences between prolactin-sparing and prolactin-elevating medications.