Porcine ESTs detected by differential display representing possible candidates for the trait 'eye muscle area'

In order to identify ESTs which represent possible candidates for carcass t raits in pigs, the differential display approach was used. F-2 animals of a resource population and pure-bred German Landrace (DL) pigs Were selected for the trait 'eye muscle area' in order to build up groups of three high a nd three performing individuals within each population. To increase the pro bability thar differentially expressed DNA fragments were not found due to the generic background bur due to differences in a few genes affecting the trait of interest, siblings were included in the high and in the low perfor ming groups. RNA was isolated from M. longissimus dorsi and four intra-litt er constrasting pools' were prepared: high performing F-2, low performing F -2, high performing DL and low performing DL. Differential display banding patterns were produced using (d)T(11)VA (V:A,C,G) and 20 arbitrary primers. Comparing the banding patterns of the four RNA pools revealed 27 nonshared bands. Here we report on the analysis of seven of these bands, including s equencing, search for homology and mapping using a somatic cell hybrid pane l. Two clones showed high homology to known genes, two were homologous to a n EST and a SINE sequence. Three clones did not show any homology. Differen tial expression was tested by semiquantitative reverse transcription-polyme rase chain reaction (RT-PCR) and could be confirmed for six clones.