Fig. 3.

The detection of normal size BTK gene expression in patient 2 but not in patient 1. (a) The abnormally smaller size PCR product in (b) and (c) was sequenced and found to be the result of a splicing abnormality caused by the mutation of intron 11. (b) The abnormally small size PCR product in the family of patient 1. The arrow indicates the normal size PCR product detected in the mother. The arrowhead indicates an abnormally small size PCR product. M: size marker; lane 1: mother of patient 1; lane 2: father of patient 1; lane 3: patient 1. (c) The abnormally small size and normal size PCR product in patient 2. The arrow indicates the normal size PCR product. The arrowhead indicates abnormally small size PCR product. M: DNA size marker; lane 1: patient 2.