Vector–Hexamer PCR Isolation of All Insert Ends from a YAC Contig of the Mouse Igh Locus

The 36 Igh YAC clones in this study are listed vertically in thetop half for the left-arm ends and in the bottom half for the right-arm ends. Hexamer primers are listed across thetop. Results of each attempt to recover a YAC insert end with vector–hexamer PCR are indicated. Reactions that did not produce any visible YAC end product are denoted X; blank cells are combinations of YAC end and hexamer primer that were not tried. For each successful reaction the size (in bp) and intensity are given for the most readily sequenceable product (those of the greatest intensity and closest to 400 bp). The yield of the PCR is indicated as intense product (∼0.5–2.0 μg) (•); medium intensity (◓) and faint product (○). Sequencing was usually successful with medium- and high-intensity fragments but only rarely with faint products. The size listed is the third-round product, which includes ∼75 bp of vector sequence. Where an end product was successfully sequenced the GenBank accession no. is given to the right of the intensity indicator. Where GenBank entries are the compilation of several sequences obtained with different hexamer primers the same accession no. appears several times in a row. In certain cases, the sequence from the vector primer did not overlap the reverse sequence from the hexamer primer and multiple accession numbers are listed for one YAC end amplification.