title: A unique combination of 17pter trisomy and 21qter monosomy in a boy with developmental delay, severe intellectual disability, growth retardation and dysmorphisms.
abstract: BACKGROUND
  Microduplication at 17p13.3 and microdeletion at 21q22 are both rare chromosomal aberrations. The presence of both genomic imbalances in one patient has not been previously reported in literature. In this study, we performed a molecular diagnostic testing with a whole genome microarray on a 3-year-old boy with developmental delay, mental retardation and multiple malformations.
  
  
  METHODS
  A routine G-banding karyotype analysis was performed using peripheral lymphocytes. Chromosome microarray analysis (CMA) was done using Affymetrix CytoScan™ HD array. Genomic imbalances were further confirmed by multiple ligation-dependent probe amplification (MLPA).
  
  
  RESULTS
  The result of karyotyping was normal but CMA detected a 9.8 Mb microduplication at 17p13.3-13.1 (chr17: 1-9,875,545) and a 2.8 Mb microdeletion involving 21q22.3-qter (chr21: 45,239,077-48,097,372). The imbalances were due to a balanced translocation present in patient's mother. The patient was characterized with short stature, profound developmental delay, non-verbal, intellectual disability as well as craniofacial dysmorphism, subtle brain structural anomaly and sparse scalp hair.
  
  
  CONCLUSIONS
  This is the first patient reported with a combination of a microduplication at 17p13.3-13.1 and a microdeletion at 21q22.3-qter. Both genomic imbalances were undetected by conventional karyotyping but were delineated with CMA test. Synergistic effect from the two rare genomic imbalances is likely responsible for the severe clinical phenotypes observed in this patient.
authors.affiliation: Department of Laboratory Medicine, Shanghai Children's Medical Center, Shanghai Jiaotong University School of Medicine, Shanghai 200127, PR China.
authors.forename: Zhaojing
authors.initials: Z
authors.lastname: Zheng
authors.forename: Ru-En
authors.initials: RE
authors.lastname: Yao
authors.forename: Juan
authors.initials: J
authors.lastname: Geng
authors.forename: Xingming
authors.initials: X
authors.lastname: Jin
authors.forename: Yongnian
authors.initials: Y
authors.lastname: Shen
authors.forename: Daming
authors.initials: D
authors.lastname: Ying
authors.forename: Qihua
authors.initials: Q
authors.lastname: Fu
authors.forename: Yongguo
authors.initials: Y
authors.lastname: Yu
mesh_terms: D000015:Abnormalities, Multiple / Q000175:diagnosis / Q000235:genetics*; D002675:Child, Preschool; D002886:Chromosomes, Human, Pair 17 / Q000235:genetics; D002891:Chromosomes, Human, Pair 21 / Q000235:genetics; D019465:Craniofacial Abnormalities / Q000150:complications / Q000175:diagnosis / Q000235:genetics*; D002658:Developmental Disabilities / Q000150:complications / Q000175:diagnosis / Q000235:genetics*; D006801:Humans; D008607:Intellectual Disability / Q000150:complications / Q000175:diagnosis / Q000235:genetics*; D008297:Male; D009006:Monosomy / Q000175:diagnosis / Q000235:genetics; D014314:Trisomy / Q000175:diagnosis / Q000235:genetics