HGF and melanoma: Nevertheless, in contrast to epidemiologic studies showing that constitutively dark human skin is less sensitive to development of UV-induced skin cancer, including melanoma, than the fair phototype, in the HGF/SF transgenic mice, the effect is reversed and black pigmented HGF/SF transgenics are more susceptible to melanoma, particularly to UVA-induced melanoma although the rate of UVB-induced melanoma formation was not altered by the presence of melanin [ 6].