Biomedical subjects

Christopher J Porter

Publications and source records attributed to Christopher J Porter.

3 recordsLinked to original sources

PubMed2005

Study of stem cell function using microarray experiments.

DNA Microarrays are used to simultaneously measure the levels of thousands of mRNAs in a sample. We illustrate here that a collection of such measurements in different cell types and states is a sound source of functional predictions, provided the microarray experiments are analogous and the cell samples are appropriately diverse. We have used this approach to study stem cells, whose identity and mechanisms of control are not well understood, generating Affymetrix microarray data from more than 200 samples, including stem cells and their derivatives, from human and mouse. The data can be accessed online (StemBase; http://www.scgp.ca:8080/StemBase/).

Animals↗

PubMed2002

Systematic evaluation of map quality: human chromosome 22.

Marker positions on nine genetic linkage, radiation hybrid, and integrated maps of human chromosome 22 were compared with their corresponding positions in the completed DNA sequence. The proportion of markers whose map position is <250 kb from their respective sequence positions ranges from 100% to 35%. Several discordant markers were identified, as well as four regions that show common inconsistencies across multiple maps. These shared discordant regions surround duplicated DNA segments and may indicate mapping or assembly errors due to sequence homology. Recombination-rate distributions along the chromosome were also evaluated, with male and female meioses showing significantly different patterns of recombination, including an 8-Mb male recombination desert. The distributions of radiation-induced chromosome breakage for the GB4 and the G3 radiation hybrid panels were also evaluated. Both panels show fluctuations in breakage intensity, with different regions of significantly elevated rates of breakage. These results provide support for the common assumption that radiation-induced breaks are generally randomly distributed. The present studies detail the limitations of these important map resources and should prove useful for clarifying potential problems in the human maps and sequence assemblies, as well as for mapping and sequencing projects in and across other species.

Chromosome Breakage↗

PubMed2002

Arab genetic disease database (AGDDB): a population-specific clinical and mutation database.

Here we present the Arab Genetic Disease Database (AGDDB), a curated catalog of genetic disorders found in Arab populations. The first release of the database is populated primarily with information from the textbook Genetic Disorders Among Arab Populations [Teebi and Farag, 1997]. AGDDB is composed of data elements revolving around disorder reports. Other reports cover clinical, genomic, reference, and population frequency elements and their important attributes. The Arab Genetic Disease Consortium (30 investigators, 18 countries) is responsible for editing and reviewing AGDDB data. After initial indexing, AGDDB contains over 1,000 unique disorder entries. Entries are linked to their counterparts in the Online Mendelian Inheritance in Man (OMIM) database; similar associations with relevant locus-specific and central mutation databases are planned. The database can be queried by keyword across all its fields, with more focused searches allowed. The database is freely available and may be accessed at www.agddb.org. The database serves as a robust prototype for cataloging variation and disorder information within a specific population.

Arabs↗