Original sentence: As with peoples that migrated northward, those with lighter skin that migrated southward had to acclimate to the much stronger solar radiation.Darker skin affords far greater protection than lighter skin against sunburn and the development of melanoma, a potentially extremely deadly form of skin cancer.Darker skin is a complicating factor in the laser removal of port-wine stains.Effective in treating lighter skin, lasers have less success in removing port-wine stains in darker skin.High melanin levels also can be a disadvantage
Edited sentence: As with peoples that migrated northward, those with light skin that migrated southward had to acclimate to the much stronger solar radiation.Dark skin affords far greater protection than fair skin against sunburn and the development of melanoma, a potentially extremely deadly form of skin cancer.Dark skin is a complicating factor in the laser removal of port-wine stains.Effective in treating Caucasian skin, lasers have less success in removing port-wine stains in Asians and blacks.In people of color, however, high melanin levels also can be a disadvantage