SIXTH SPECIAL AWARD 367 I wish to congratulate the Soc•v.T¾ OF Costar. Tin C•Emsq's, which has honored both itself and Dr. Lerner in its choice of the 1960 recipient of its award. I cannot even begin to express my pride in the accomplish- ments of this man who started his graduate career in my small laboratory at Minnesota. I can only say, "Aaron, you've done a damned good job!" SKIN COLOR By AARON B. LERNER, M.D. AI•i• or us are aware of the great importance of skin color from socio- logic, cosmetic and protective standpoints. Several years ago a soci- ologist, himself a Negro, emphasized to me that the single most important characteristic to know about a person is his color. That is, skin color is even more important than age or sex. Usually there are no cosmetic prob- lems pertaining to pigmentation as long as one possesses uniform coloring. However, an abnormal increase or decrease in melanin pigmentation, either in a patchy or homogeneous distribution, always is of great concern to the affected individual. In some instances these pigment changes may indicate the existence of a systemic disease. Protection of the skin from sunlight is maintained largely through the presence of melanin in the epidermis. In spite of some claims that keratin thickening is the major source of light protection, it is probable that the most important barrier to light damage is melanin. For all these reasons it is necessary to know how melanin is formed and how various factors produce abnormalities in pigmentation. In man the copper-containing enzyme, tyrosinase, catalyzes the oxidation of tyrosine to melanin in the cytoplasm of melanocytes. Tyrosinase can be made more active by exposing the skin to sunlight. Oral ingestion of psoralen de- rivatives before light exposure will markedly enhance new pigment forma- tion. Another but not desirable way of increasing tyrosinase action is administration of inorganic arsenic. Recently it wa• shown that injection of the melanocyte stimulating hormones (a- and •-MSH) obtained from the pituitary gland can produce marked darkening. This augmentation of skin color probably results from both an increase in the dispersion of melanin granules throughout the cytoplasm of melanocytes and from an increase in tyrosinase action. In pregnant women, in patients with adreno- cortical insufficiency and in some patients with pituitary tumors hyper- pigmentation develops largely on the basis of increased release of MSH from the pituitary gland. A few patients with malignant melanoma develop

368 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS intense hyperpigmentation because of excessive tyrosinase action in the metastatic tumors. When there is a lack of tyrosinase, as in albinism, melanin cannot form. However, the etiology of gray hair and vitiligo is unknown. Melatonin, recently isolated from bovine pineal glands, is a potent lighten. ing agent of frog and fish melanocytes and may play a role in the hypopigmentation of vitiligo and gray hair. It is of interest that melatonin, which was studied primarily for its ability to lighten frog melanocytes, is the first methoxyindole to be found in mammalian tissue and the first N-acetyl com- pound that has greater biologic activity than the amine from which it was derived. To what extent can we control skin color? It is possible to produce marked hyperpigmentation in many people by using either the psoralens orally followed by exposure of the skin to sunlight or by injecting MSH. Although MSH works quite well it is difficult to get this material at the present time. A nonmelanin type of hyperpigmentation may be obtained by applying one of the dihydroxyacetone products to the skin. Often it is possible to produce desired hyperpigmentation i• normal per- sons. But it is not yet possible to initiate controlled hypopigmentation. In some individuals monobenzylether of hydroquinone applied locally will cause depigmentation. However, this chemical is not always consistent in its action and it is a sensitizing agent. It is still too early to know what melatonin will do. From basic considerations it is reasonable to expect that some day it may be practical to lighten or darken skin color at will. A SURVEY OF DR. AARON B. LERNER'S CONTRIBUTIONS TO THE KNOWLEDGE OF MELANIN AND MELANOGENESIS IN ORDER TO ACQUAINT the membership of the SOCiETy or COSMETIC C•,EM•STS more fully with the scientific contributions of the 1959 Special Award winner, Dr. Aaron B. Lerner, the Literature Review Committee has prepared the following summary of Dr. Lerner's work. Dr. Lerner's contributions to our knowledge of melanin biochemistry be- gan in 1940 while he was doing some research under the direction of Dr. L. Earle Arnow. However, for a more complete understanding, it will be necessary to include some earlier studies. For almost sixty years (1), it has been recognized that melanin is formed intracellularly from tyrosine by enzymatic oxidation. The enzyme tyrosinase, the catalyst for the oxida- tion of tyrosine, has been identified in plants, insects and marine animals.