FTLS patient and control genomic DNA/cDNA libraries were constructed according to the manufacturer's instructions (Illumina). In brief, RT-PCR and PCR products were roughly quantified by UV absorption and equal amounts of each sample were mixed. Nucleic acids within the mixtures were sheared by sonication, and fragments in the 150-180-bp range were collected by cutting bands from an agarose gel after electrophoresis. The sheared DNA and cDNA ends were repaired using Klenow DNA polymerase, after which 5' termini were phosphorylated and 3' termini were polyadenylated. The adaptors were added, PCR enrichment was performed, and 150-180-bp fragments were collected for sequencing by the Illumina method.