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Andrew T DeWan

Publications and source records attributed to Andrew T DeWan.

4 recordsLinked to original sources
PubMed2026

Gene-Temperature Interactions and Risk of Childhood Acute Lymphoblastic Leukemia.

BACKGROUND: High ambient temperature in early pregnancy has been linked to an increased risk of childhood acute lymphoblastic leukemia (ALL). To better understand biological mechanisms, the current study evaluated potential interaction between temperature and genetic characteristics. METHODS: We used data from California birth records (1982-2008) and California Cancer Registry (1988-2011) to identify ALL cases (n=3,353) diagnosed &#x2264;14 years of age and non-cancer controls (n=3,530) matched 1:1 on sex, race, ethnicity, and birth year and month. Weekly ambient temperatures throughout pregnancy were assessed on a 1-km grid around the birth address, while genetic data were available from a genome-wide association study using neonatal blood spots. We evaluated the association between ambient temperature and ALL risk by quartiles of established genetic risk score for ALL. Next, we formally tested gene-temperature interactions in the association with ALL, correcting for multiple testing, for genes previously identified with epigenetic changes due to both temperature and ALL. All analyses were adjusted for potential confounders. RESULTS: The elevated risk of ALL per 5 &#xb0;C increase of weekly mean ambient temperature, confined to early pregnancy, was more pronounced among children with the lowest genetic susceptibility to ALL, especially among Latino children (first quartile: odds ratio [OR] = 1.50, 95% confidence interval [CI]: 1.14-1.97); fourth quartile: OR=1.03, 95% CI: 0.83-1.28). There were significant interactions (p<0.002) between ambient temperature and polymorphisms in BNC1 among non-Latino White children, and suggestive interactions (p<0.05) with TBPL2 and NRXN1 in the full population. CONCLUSIONS: Our findings suggest that there may be interactions between ambient temperature in early pregnancy and offspring genotype in the risk of childhood ALL. IMPACT: If replicated, these findings could help elucidate the biological mechanisms linking high ambient temperature in early pregnancy and the risk of childhood ALL.

Journal Article↗
PubMed2002

Map error reduction: using genetic and sequence-based physical maps to order closely linked markers.

The Marshfield comprehensive genetic maps are frequently used for linkage and association studies, however, for some regions of these maps the marker order has low level of likelihood ratio support. In order to investigate the level of statistical support and the accuracy of the genetic maps compared to sequence-based physical maps, two approximately 30 cM autosomal regions were selected. The first region was selected from chromosome 3 and consisted predominately of draft sequence. The second region was selected from chromosome 21 and consisted of finished sequence data. The physical order of these markers was based upon their position on Celera (CEL) and Human Genome Project-Santa Cruz (HGP-sc) sequence-based physical maps. The chromosome 3 and 21 regions contained 100 and 61 markers, respectively, on the Marshfield genetic map. The genetic and physical map order was consistent for 88.9 and 89.2% of the markers in the region on chromosome 3 and 21, respectively. Using a novel scoring criterion to assess inconsistent marker order between genetic and physical maps, it was determined that the physical order was likely the correct order for 3.3 and 7.1% of the markers in the chromosome 3 and 21 regions, respectively. To increase the accuracy of the order of markers selected for fine mapping a method is presented which combines information from genetic and sequence-based physical maps.

Genetic Linkage↗
PubMed2001

The map problem: a comparison of genetic and sequence-based physical maps.

The genetic order of autosomal genome-scan markers from Marshfield panels 9 and 10 were compared with their physical order, on the basis of the assembled nonredundant human genome sequence from the Human Genome Project-Santa Cruz (HGP-sc; October 2000 and April 2001 releases) and Celera (CEL; February 2001 release) databases. The genetic order of 96% of the markers on the Marshfield map for panel 10 is supported by a likelihood ratio of > or = 3 (odds ratio of 1,000:1). Inconsistencies with the genetic panel 10 map were found for 5% and 2% of the markers in the CEL and HGP-sc sequences, respectively. These inconsistencies consisted of both positional and chromosomal-assignment disagreements. For the majority of these inconsistent markers, the genetic order was supported by a likelihood ratio of > or = 3, and the physical order in the other assembly matched the genetic order. The majority of the inconsistencies between the physical- and genetic-map order point to errors in the physical-map order. A Web site is made available that displays inconsistencies for genetic markers from Marshfield panels 9 and 10 between their genetic-map positions and sequence-based physical-map positions, as well as inconsistencies between their sequence-based physical position. This Web site also contains genetic-map distances, physical-map positions from the Celera and Human Genome Project sequence, and likelihood-ratio support for the genetic maps.

Chromosome Mapping↗