Inherited partial direct duplication of 11q: First report and possible association with a midline developmental field defect
- Kaiser Permanente, San Jose, CA (United States); and others
A 36-year-old woman underwent amniocentesis for advanced maternal age. The fetal karyotype had an extra dark staining G band on the long arm of chromosome 11 with no other identifiable abnormalities. FISH studies using a chromosome 11 paint probe confirmed the origin of the extra band. The abnormality was identified as a partial duplication of 11q: 46,XX dir dup (11)(q13.5q21) or (q21q23.1). The specific duplicated band could not be identified with certainty. Detailed fetal sonograms were normal. Family studies revealed the identical duplication in the mother but normal karyotypes in both maternal grandparents. The mother had strabismus and a short tongue frenulum which required surgical correction. Menses occurred late in adolescence and complete development of secondary sexual characteristics was delayed until adulthood. An infertility evaluation revealed duplication of the uterus, cervix, and vagina. An evaluation for metorrhagia identified a pituitary adenoma which was resected. Her intelligence was normal. To our knowledge this is the first report of a heritable direct duplication of 11q. It is possible that one or more gene in the duplicated segment played a causal role in the pathophysiology of the patient`s anomalies through a disturbance of the so-called {open_quotes}midline developmental field{close_quotes}. Alternatively, the cytogenetic findings could be unrelated to the malformations. Rare instances of partial gain or loss of specific late-replicating heterochromatic regions without phenotypic effect have been reported. This region of 11q is also relatively late-replicating. This is consistent with previous reports suggesting a paucity of expressed genes in this 11q region. Molecular studies of the duplication are underway to determine the specific location and extent of duplication. Phenotypic evaluation of the patient`s baby will also be reported.
- OSTI ID:
- 133781
- Report Number(s):
- CONF-941009-; ISSN 0002-9297; TRN: 95:005313-0514
- Journal Information:
- American Journal of Human Genetics, Vol. 55, Issue Suppl.3; Conference: 44. annual meeting of the American Society of Human Genetics, Montreal (Canada), 18-22 Oct 1994; Other Information: PBD: Sep 1994
- Country of Publication:
- United States
- Language:
- English
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