title: [Diagnosis of MECP2 duplication syndrome with molecular genetic techniques].
abstract: OBJECTIVE
  To investigate whether the four boys with delayed motor development and intellectual disability suffer from MECP 2 duplication syndrome.
  
  
  METHODS
  Blood specimens and clinical data of four patients and mothers of patient 2 and patient 4 were collected. Genomic DNA was extracted from peripheral blood using DNA extraction kit. At first multiplex ligation-dependent probe amplification (MLPA) was employed in 4 patients, two distinct kits SALSA P036 and P070 for sub-telomere screening, and SALSA P245 for the 22 common microdeletion and microduplication syndromes. Then array-CGH analysis was carried out. Two mothers of patients were tested by array- comparative genomic hybridization (CGH) and X chromosome inactivation analysis.
  
  
  RESULTS
  All the 4 patients presented with severe hypotonia, delayed motor development, intellectual disability and absent or limited language. Three patients manifested recurrent pneumonia in infancy except patient 2. Four patients had duplication on chromosome Xq28 with MLPA kit SALSA P245. Array-CGH identified the size of each duplication on Xq28. The precise size of each duplication was different in the four patients: patient 1, 14.931 Mb, patient 2, 0.393 Mb, patient 3, 0.482 Mb and patient 4, 0.299 Mb. To compare Xq28 duplications with UCSC database (http://genome.ucsc.edu/) revealed that each duplication harbors the MECP 2 and HCFC 1 gene. Mothers of patient 2 and patient 4 also carried microduplication on Xq28. X chromosome inactivation analysis demonstrated completely skewed inactivation (0: 100) and it is the inactive allele that passed on to the patients.
  
  
  CONCLUSIONS
  For patients that present with delayed motor development, intellectual disability, hypotonia, absent or limited language and recurrent infection, combination of MLPA and array- CGH is effective and specific diagnostic methods of MECP 2 duplication syndrome.
authors.affiliation: Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China.
authors.forename: Zhi
authors.initials: Z
authors.lastname: Yi
authors.affiliation: Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China.
authors.forename: Songtao
authors.initials: S
authors.lastname: Wang
authors.affiliation: Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.affiliation: Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China.
authors.forename: Hairong
authors.initials: H
authors.lastname: Wu
authors.affiliation: Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China.
authors.forename: Yinan
authors.initials: Y
authors.lastname: Ma
authors.affiliation: Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Qi
authors.affiliation: Department of Central Laboratory, Peking University First Hospital, Beijing 100034, China. Email: panmuren@263.net.
authors.forename: Hong
authors.initials: H
authors.lastname: Pan
mesh_terms: D041321:Chromosomes, Human, X / Q000235:genetics; D055028:Comparative Genomic Hybridization; D020440:Gene Duplication; D006801:Humans; D008297:Male; D038901:X-Linked Intellectual Disability / Q000175:diagnosis* / Q000235:genetics*; D051783:Methyl-CpG-Binding Protein 2 / Q000235:genetics; D060885:Multiplex Polymerase Chain Reaction; D049951:X Chromosome Inactivation
chemical_list: D051783:Methyl-CpG-Binding Protein 2