Proximal 6q interstitial deletion without severe mental retardation.
Deletions of the proximal portion of the long arm of chromosome 6 are rare, and the patients reported in the literature have been described as having significant mental retardation, often in the severe to profound range. We report on a young girl with a proximal 6q interstitial deletion [46, XX, del (6) (q1 3q15)] who exhibits the typical morphological and neurological manifestations except that the degree of language and non-language cognitive delay is mild. Cognitive development has been assessed using the Capute Scales. Gross motor development has been assessed clinically using standard milestones. At 34 months of age, she was found to have severe gross motor delay, with mildly delayed non-language cognitive abilities and expressive language abilities. Her receptive language skills tested in the average range. In recent years. several forms of autosomal dominant drusen and macular degeneration have been mapped to 6q14, and substantial variability in clinical expression has been described. Serial ophthalmologic examinations have not detected any drusen or atrophic macular changes in our patient. To our knowledge, this is the first description of a child with proximal 6q interstitial deletion in the documented absence of severe cognitive deficiency. This information may be important to clinicians who counsel families of infants determined to have proximal 6q interstitial deletions. Because the deleted region contains the area to which autosomal dominant drusen and macular degeneration has been mapped, we believe that this child is at risk for visual loss, and she will continue to be monitored closely.
Myers
S M
SM
Division of Neurodevelopmental Pediatrics, Department of Pediatrics, Geisinger Medical Center, Danville, PA 17822-1339, USA. smyers1@geisinger.edu
Challman
T D
TD
D000015:Abnormalities, Multiple; D002675:Child, Preschool; D002872:Chromosome Deletion; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics*; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000175:diagnosis* / Q000235:genetics*; D008268:Macular Degeneration / Q000235:genetics; D012720:Severity of Illness Index