Full Karyotype Interphase Cells Analysis

Heinz-Ulli Weier 1 , Adolf Baumgartner 1,2 , Chun-Mei Lu 1 , Cengiz Cinnioglu 3, *,

Lisa Chu 1 , Jingly F. Weier 1,2 , Tomas Escudero 3 and Santiago Munne 3

1 UC E.O. Lawrence Berkeley National Lab, Berkeley, CA; 2 UCSF, San Francisco, CA; 3 Reprogentics, LLC, South San Francisco, CA.

Early human development depends on the correct temporal and spatial expression of thousands of genes.   The presence of an extra or a missing chromosome in gametes typically leads to failed fertilization or spontaneous abortions. Many patients suffering from reduced fertility receive help in reproduction through in vitro fertilization(which increases the number of embryos available for replacement) followed by 'Preimplantation Genetic Diagnosis (PGD)'(which allows the selection of those embryos that are chromosomally normal). PGD is based on interphase cell analysis using fluorescence in situ hybridization (FISH). However, current FISH technology can only detect a limited number of chromosomal abnormalities. To overcome this limitation, we are developing a novel FISH protocol with Spectral Imaging (SIm) technology which utilizes 3 sets of 8 uniquely-labeled, chromosome-specific DNA probes in three sequential rounds of hybridization that allows the analysis of all 24 chromosomes in a single cell. Due to the high cost of SIm equipment, we will adapt this new protocol to regular fluorescence microscopes.