A neomycin resistance cassette (neo) was inserted into exon 2 of the gene at the NsiI site. This targeting construct was designed to disrupt Hyal3 while having minimal impact on an overlapping gene, Nat6 (N-acetyltransferase 6), which second exon is embedded within the first intron of this gene. RT-PCR analysis showed that no wild type transcript is expressed from this allele, and that Fus2 trasncripts are not altered in testis, but the levels are reduced about 20% in liver. (J:144606)