Trisomy 18: studies of the parent and cell division of origin and the effect of aberrant recombination on nondisjunction

Journal Article · Wed Mar 01 04:00:00 EST 1995 · American Journal of Human Genetics

OSTI ID:70444

Fisher, J M; Harvey, J F; Jacobs, P A ^[1]; Morton, N E ^[2]

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1. Salisbury District Hospital (United Kingdom)
2. CRC Epidemiology Research Group, Southampton (United Kingdom)

We have studied the mechanism of origin of 63 cases of trisomy 18. In 2 the additional chromosome was paternal in origin, and in the remaining 61 it was maternal in origin. Both paternal cases were attributable to a postzygotic mitotic (PZM) error. Among the 54 maternal cases for which the cell division of error was established, only 16 were attributable to an error at the first meiotic division (mat MI), whereas no fewer than 35 were due an error at the second meiotic division (mat MII), the remaining 3 being the result of a PZM error involving the maternal chromosome 18. A standard map of chromosome 18 was constructed and compared with the nondisjunctional map. Approximately one-third of the mat MI errors were associated with complete absence of recombination, whereas in the remaining two-thirds and in all the mat MII errors recombination in the nondisjoined chromosomes appeared to be normal. All the maternal errors were associated with an increased maternal age, although this reached significance only for the mat MII category of nondisjunction. Our observations on chromosome 18 are compared with those on other chromosomes for which there are comparable data. 37 refs., 7 tabs.

• OSTI ID: 70444
• Journal Information: American Journal of Human Genetics, Journal Name: American Journal of Human Genetics Journal Issue: 3 Vol. 56; ISSN AJHGAG; ISSN 0002-9297
• Country of Publication: United States
• Language: English

Related Subjects

55 BIOLOGY AND MEDICINE
BASIC STUDIES
AGE DEPENDENCE
ANIMAL CELLS
CELL DIVISION
CHROMOSOMAL ABERRATIONS
GENE RECOMBINATION
GENES
GENETIC MAPPING
GENETICS
HEREDITARY DISEASES
HUMAN CHROMOSOME 18
MUTATIONS
NON-DISJUNCTION
PATIENTS