Abstract: The invention provides improved methods of introducing site-directed mutations into circular DNA molecules of interest by means of mutagenic primer pairs. The mutagenic primer pairs are also selected so as to be either completely complementary or partially complementary to each other, wherein the mutation site (or sites) is located within the region of complementarity. A mutagenic primer pair is annealed to opposite strands of a circular DNA molecule containing the DNA sequence to be mutagenized. After annealing, first and second mutagenized DNA strands, each incorporating a member of the mutagenic oligonucleotide primer pair is synthesized by a linear cyclic amplification reaction. After the linear cyclic amplification mediated synthesis step is completed, the reaction mixture is treated with a selection enzyme that digests the parental template strands. After the digesting step, a double-stranded circular DNA intermediate is formed.

Abstract: Described herein is a novel gene and its product, WIP, which associates with WASP. The subject invention relates to the isolated WIP gene or cDNA and transgenic mammals that have the WIP gene disrupted in their genome. Also the subject of this invention are methods of treating conditions or diseases in which WIP and/or WASP DNA or protein is deficient and/or defective, for example, mutated or altered, such that an individual is adversely affected. Also described are methods of altering or regulating WIP and its functions in a mammal or in a cell of a mammal, for example in a lymphocyte. A further subject of this invention is an assay to identify drugs which alter the activity of WIP or expression of WIP DNA.