Spindle microtubular dysfunction in mothers of Down syndrome children.

Trisomy 21, Down syndrome, is more prevalent in the children of older mothers and thus theories relating to its induction have suggested alterations in reproductive physiology, sexual performance, or accumulated errors as explanations. Such theories largely neglect observations demonstrating mitotic errors in the parents and families of children with Down syndrome, which suggest that a mechanism of chromosome error, basic to both mitosis and meiosis, may exist in Down syndrome parents. This paper describes such a mechanism of error and concludes that Down syndrome parents may have a condition of microtubular dysfunction which contributes to an increased rate of hyperploidy in all their dividing cells. It is suggested that sporadic microtubular dysfunction may occasionally be induced in otherwise "non-susceptible" individuals.