Expression analysis of Wnt genes. RT-PCR analysis of fetal tissue (A) and hematopoietic stem/progenitor cells and cell lines (B). Wnt-specific primers (described in Materials and Methods) were used for PCR amplification of cDNA from brain, heart, intestine, kidney, liver, lung, thymus, ABM CD34⁺Lin⁻ hematopoietic stem/progenitor cells, B-cell lines (Daudi, Ramos, Raji), a T-cell line (Jurkat), myeloid cell lines (KG-1, KG-1A), and erythroid cell lines (HEL, TF-1). Each tissue was performed in duplicate with or without the addition of RT in the cDNA synthesis step. The PCR results for each tissue in the absence of RT was identical and is shown for only one tissue (−RT) for each set of samples. The cDNA synthesized from each tissue was divided into four equivalent portions and amplified with primers toWnt-5A (5A), Wnt-2B (2B), Wnt-10B (10B), and GAPD. In addition, for each PCR primer pair a no template control was also performed. No product was detected in any no template control (data not shown) or in any control with RT omitted (−RT, and data not shown).