They are almost always white but can often have a light to dark brown tint (known as 'biscuit'), usually around the tips of the ears. The breed can be affected by a genetic disease known as Samoyed hereditary glomerulopathy, a kidney disease. They are almost always white but can often have a light to dark brown tint (known as 'biscuit'), usually around the tips of the ears. The breed can be affected by a genetic disease known as Samoyed hereditary glomerulopathy, a kidney disease. The disease is known to be caused by an X-linked dominant faulty allele and therefore the disease is more severe in male Samoyeds. Also known as hereditary nephritis, it is caused by a nonsense mutation in codon 1027 of the COL4A5 gene on the X chromosome (glycine to stop codon), which is similar to Alport's syndrome in humans.