BMC Genomics 2005, 6:130 http://www.biomedcentral.com/1471-2164/6/130 EFxigpurersesi3on of genes clustered in 1q21, in normal cervical tissues Expression of genes clustered in 1q21, in normal cervical tissues. One hundred nanograms of total RNA purified of each sample was used in one RT-PCR reaction with gene specific primers; then one tenth of each RT-PCR reaction was sub- jected to agarose gel electrophoresis. MW: molecular weight marker; C1–C6 six different normal cervical samples to uterine myomatosis. All patients were in reproductive age and none of them received hormonal therapy or con- traceptives. All the described procedures were evaluated and approved by the local ethics committee of the Mexi- can Institute of Social Security. Written informed consent was obtained from all the patients. All tissue samples were longitudinally divided in three sections, the central part was snapped frozen in liquid nitrogen and stored at -70°C until nucleic acid extraction, and the other two were fixed overnight in 70% ethanol and were paraffin embedded at the Department of Pathology, Oncology Hospital, Table 4: Oligonucleotides sequences used in this work. National Medical Center SXXI, Mexico. Serial sections from these fractions stained by Haematoxilin/ Eosin were inspected for representativity of the tissue. HPV detection and typing Genomic DNA was extracted from the phenol phase left by the TRIzol reagent (Gibco BRL, USA) RNA isolation protocol and amplified by PCR with MY11/MY09 primers [36] (Table 4). PCR products were separated by electrophoresis on 1% agarose gel. Only HPV negative samples were included in this study. Gene Sense (5'→3') Antisense (5'→3') Annealing temperature (°C)a Product size (bp) HPV* GCMCAGGGWCATAAYAATGG S100 A8 ATGCCGTCTACAGGGATGAC S100 A9 TCAGCTGGAACGCAACATAGA SPRR3 TTCCACAACCTGGAAACACA NICE-3 ACGGCTATGAAACAGCCCGCTA NICE-4 ACGGAATCCAATGAGGAAGGCA GAPDH CATCTCTGCCCCCTCTGCTGA CGTCCMARRGGAWACTGATC ACGCCCATCTTTATCACCAG TCAGCTGCTTGTCTGCATT TTCAGGGACCTTGGTGTAGC GCACATTGCAACTGACTGGCTT TCAGTATTGGCTGGCTCTGCAT GGATGACCTTGCCCACAGCCT 55 58 56 55 57 57 60 aTm was calculated using primerquest program from [39]; however, it was necessary to adjust Tm in some cases. 450 160 205 174 330 294 205 Reference [36] This paper This Paper This paper This paper This paper [38] Page 7 of 9 (page number not for citation purposes)