Nonrandom chromosomal abnormalities in hematologic disorders of man

A nonrandom pattern of chromosomal abnormalities occurs in bone marrow cells obtained from patients with hematologic disorders who have an abnormal karyotype involving a C group chromosome. An additional number 8 chromosome is the most common abnormality, found in more than one-half of the patients studies. An additional number 9 chromosome and the loss of all or part of a number 7 are abnormalities that occur more often than might be expected by chance. It is proposed that specific human chromosomal abnormalities may be related to different specific etiologic agents.