title: Isolated trisomy 7q21.2-31.31 resulting from a complex familial rearrangement involving chromosomes 7, 9 and 10.
abstract: BACKGROUND
  Genotype-phenotype correlations for chromosomal imbalances are often limited by overlapping effects of partial trisomy and monosomy resulting from unbalanced translocations and by poor resolution of banding analysis for breakpoint designation. Here we report the clinical features of isolated partial trisomy 7q21.2 to 7q31.31 without overlapping phenotypic effects of partial monosomy in an 8 years old girl. The breakpoints of the unbalanced rearranged chromosome 7 could be defined precisely by array-CGH and a further imbalance could be excluded. The breakpoints of the balanced rearranged chromosomes 9 and 10 were identified by microdissection of fluorescence labelled derivative chromosomes 9 and 10.
  
  
  RESULTS
  The proband's mother showed a complex balanced translocation t(9;10)(p13;q23) with insertion of 7q21.2-31.31 at the translocation breakpoint at 9p13. The daughter inherited the rearranged chromosomes 9 and 10 but the normal chromosome 7 from her mother, resulting in partial trisomy 7q21.2 to 7q31.31. The phenotype of the patient consisted of marked developmental retardation, facial dysmorphism, short stature, strabism, and hyperextensible metacarpophalangeal joints.
  
  
  CONCLUSIONS
  For better understanding of genotype-phenotype correlation a new classification of 7q duplications which will be based on findings of molecular karyotyping is needed. Therefore, the description of well-defined patients is valuable. This case shows that FISH-microdissection is of great benefit for precise breakpoint designation in balanced rearrangements.
authors.affiliation: Department of Obstetrics and Gynaecology, Christian-Albrechts-University of Kiel, University Hospital of Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str.3, Haus 24, Kiel, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Weimer
authors.affiliation: Institute of Human Genetics, Christian-Albrechts-University of Kiel, University Hospital Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str.3, Haus 10, Kiel, Germany.
authors.forename: Simone
authors.initials: S
authors.lastname: Heidemann
authors.affiliation: Department of Obstetrics and Gynaecology, Christian-Albrechts-University of Kiel, University Hospital of Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str.3, Haus 24, Kiel, Germany.|Department of Obstetrics, Gynaecology and Reproductive Medicine, Hannover Medical School, Hannover, Germany.
authors.forename: Constantin S
authors.initials: CS
authors.lastname: von Kaisenberg
authors.affiliation: Institute of Human Genetics, Christian-Albrechts-University of Kiel, University Hospital Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str.3, Haus 10, Kiel, Germany.
authors.forename: Werner
authors.initials: W
authors.lastname: Grote
authors.affiliation: Department of Obstetrics and Gynaecology, Christian-Albrechts-University of Kiel, University Hospital of Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str.3, Haus 24, Kiel, Germany.
authors.forename: Norbert
authors.initials: N
authors.lastname: Arnold
authors.affiliation: Institute of Human Genetics, Christian-Albrechts-University of Kiel, University Hospital Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str.3, Haus 10, Kiel, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Bens
authors.affiliation: Institute of Human Genetics, Christian-Albrechts-University of Kiel, University Hospital Schleswig-Holstein, Campus Kiel, Arnold-Heller-Str.3, Haus 10, Kiel, Germany.
authors.forename: Almuth
authors.initials: A
authors.lastname: Caliebe