Another study reported that nonablative fractional lasers induced the growth of intact hair in three adult patients with ARWH.9 Recently, four patients with hypotrichosis simplex of the scalp were treated successfully with topical gentamycin.10 They showed that gentamicin induced in vitro read-through activity across a CDSN mutation that causes hypotrichosis simplex. This evidence concerns the gene CDSN and hypotrichosis simplex.