This site provides [1] information on Down syndrome, [2] raw data and supplementary information for Mao et al. (Genomics 2003 May, 81(5)) "Global up-regulation of chromosome 21 gene expression in the developing Down Syndrome brain" (pdf) and [3] raw and supplementary data for Mao et al. (submitted, 2005), "Role of gene expression in the developing human Down syndrome brain and heart" (pdf).


For our 2003 and 2005 gene expression papers, we used the following approaches:

- analyze frozen brain and heart samples obtained from fetal abortuses of 17-20 gestational weeks age (see brain data on DS home page);

- analyze astrocyte cell lines derived from fetal brains of 17-20 gestational weeks age (see astrocyte data on DS home page).

Total RNA was extracted from the samples and the expression levels of up to 18,462 transcripts, representing approximately 15,106 genes, were quantified using Affymetrix microarrays (human U95Av2 or U133A).

For our data analysis, we employed Partek Pro software (, SNOMAD, and DRAGON.



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Last updated: December 30, 2005.