The phenotype and cytogenetic findings associated with a de novo tandem inverted triplication of distal chromosome 1q from 1q42-44 are described in this report of an 18-month old female. To our knowledge, this chromosome aberration has not been previously reported as a constitutional anomaly.Labor was induced at 36 wks for polyhydramnios. The parents were healthy unrelated 18 year olds at delivery. Birth weight was 2.44 kg. The infant had respiratory distress with absent epiglottis, tracheolaryngomalacia and micrognathia. Duodenal stenosis, ASD, pulmonary hypertension, dilated lateral venticles and dysmorphic facies were noted. Chromosome analysis was done in the newborn period. Later G tube, fundal plication and tracheostomy were needed for swallowing dysfunction and aspiration pneumonia. At 18 months, she is now O2 dependent and chronically ventilated with recurrent pulmonary edema. She lives in a chronic care facility where she is making slow developmental progress. She recognizes her caretaker, responds to her name, smiles and rolls over. She claps but has little purposeful use of her hands. All growth parameters are at the 50th%ile or above. On examination she is chubby with brachycephaly, a round face, epicanthus inversus, exotropia of the left eye, small mouth and retrognathia. Her facies are not strikingly dysmorphic. Her fingers are tapered with well-developed fetal pads and normal flexion creases. She has long dark pubic hairs. Her neurological exam is pertinent for hypotonia, tactile defensiveness, social awareness with stranger anxiety and avoidance of eye contact. FISH studies with whole chromosome paint confirmed that the extra material was derived from chromosome 1. The telomere probe D1S3738 hybridized to the abnormal ch1q. G-banding at the 600 band level was consistent with a tandem inverted triplication of the segment 1q42-44. Parental chromosome studies were normal. Comparative genome hybridization studies are planned. Dup 1q42-44 is an uncommon chromosome anomaly and triplication of this segment has not been reported previously. The phenotype of dup1q42-44 has been described as “mild with near normal intelligence.” This may explain the absence of severe malformations and the relative lack of dysmorphic features in this child with triplication of the same segment. The dup1q42-44 phenotype will be reviewed and compared with the present case.
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