Figure 3.

CLD mutations in the LCT gene. A–E, DNA sequence chromatograms of five identified CLD mutations. One mutation, Y1390X, (A) is a homozygote, whereas the rest of the mutations are heterozygotes. The first row shows affected sequences and the second row wild-type sequences. In addition, c.655G→A, a SNP (rs3754689) leading to V219I, is shown in panel E (Boll et al. 1991). PCR was performed using the genomic DNA-amplifying promoter region, exons, flanking intron sequences, and 3′-UTRs of the LCT gene (primers are available on request). Sequencing was performed in both directions, and the sequenced products were electrophoresed on an ABI 3730 DNA analyzer (Applied Biosystems) in accordance with the manufacturer’s instructions and were analyzed using ABI Sequencing Analysis 3.3 (Applied Biosystems) and Sequencher 4.1 (Gene Godes).