Gene expreion variation in the adult human retina

Depite evidence that difference in gene expreion level contribute ignificantly to phenotypic variation acro individual, there ha been only limited effort to tudy gene expreion variation in human tiue. To characterize expreion variation in the normal human retina, the author utilized a cutom retinal microarray to analyze 33 normal retina from 19 donor, aged 29 to 90 year. tatitical model were deigned to eparate and quantify biological and technical ource of variation, including age, gender, eye laterality, gene function, and age-by-gender interaction. Although the majority of the 9406 gene analyzed howed relatively table expreion acro different donor (for an average gene the expreion level value of 95 out of a 100 individual fell within a 1.23-fold range), 2.6% of gene howed ignificant donor-to-donor variation, with a fale dicovery rate of 10%. The mean expreion ratio tandard deviation wa 0.15 ± 0.8, log2, with a range of 0.09 to 0.99. Gene electively expreed in photoreceptor howed higher expreion variation than other gene clae. Gender, age, and other donor-pecific factor contributed ignificantly to the expreion variation of multiple gene, and group of gene with age- or gender-aociated expreion pattern were identified. Thee finding how that a ignificant fraction of gene expreion variation in the normal human retina i attributable to identifiable biologic factor. The greater expreion variability of many gene central to retinal function (including photoreceptor-pecific gene) may be partially explained by the dynamic of the viion proce, and raie the poibility that photoreceptor gene expreion level may contribute to phenotypic diverity acro normal adult retina. Additionally, a uch diverity may reult in different level of dieae uceptibility, exploring it ource may provide inight into the pathogenei of retinal dieae.—Han E. Groniklau