A A NUMBER of years ago, it was incidentally observed that many patients with sickle cell disease had an "extra" transverse dermal crease on the palmar surface of the digits situated just beyond the distal interphalangeal flexion creases. These were present at birth, persisted with subsequent growth, and were most frequently noted on the middle finger. Recently, when identification of hemoglobins by electrophoresis became available, it was decided to employ this technique as a basis for evaluating the validity of this peculiar physical sign in clinical recognition of sickle cell disease.
Prints suitable for interpretation were secured from 130 subjects. Eighty-six had classical clinical manifestations of sickle cell disease with S-hemoglobin as a single band, or with quantitative S-hemoglobin de-
terminations greater than 60% by electrophoresis. The 44 controls had no clinical evidence of sickle cell disease and normal electrophoretic patterns. Table 1 shows distribution of both groups by sex,