Increased Q fluorescence of an inactive Xq-chromosome in man.

Abstract

The proposita's main characteristics were primary amenorrhea, lack of secondary sexual development, shortness of stature, and shield chest. Her 46 chromosomes included one normal X and an X chromosome with a partially deleted long arm. The abnormal chromosome was late labeling and formed a smaller than normal Barr body. It was almost always more brightly fluorescent than the normal X chromosome in the same cell, especially in the faintly fluorescent region around the centromere. The short arm of the abnormal chromosome was also significantly shorter than that of the normal X chromosome.