Gene Expression in the Human Mammary Epithelium during Lactation: the Milk Fat Globule Transcriptome through 4 Days

The 4 day gene expression profile in the lactating mammary gland was demonstrated using the Human Ref-8 BeadChip array (Illumina, Inc). Of the 22,184 gene transcripts on the array, 14,070 genes were consistently expressed and represented the milk fat globule transcriptome. Milk protein genes were among the most highly expressed along with genes involved in the milk syntesis processes. Serial milk samples were collected every 3h for 4 days from 5 normal, lactating women. RNA was isolated from the milk fat globules and utilized for microarray analyses.