This medical illustration depicts the symptoms of Klinefelter's Syndrome, a congenital male chromosomal abnormality which occurs in approximately 0.002% of male births, resulting in an XXY configuration rather than the typical XY. The addition of the X sex chromosome produces the following characteristics: tendency to grow less body hair, small testicular (testes) size, long arms and legs, narrow shoulders, poor beard growth, female pubic hair pattern, and narrow shoulders.