Lili Zhou1, Zhaoke Zheng1, Yunzhi Xu1, Xiaoxiao Lv1, Chenyang Xu1, Xueqin Xu2. 1. Center of Prenatal Diagnosis, Wenzhou Central Hospital, Wenzhou, 325000, People's Republic of China. 2. Center of Prenatal Diagnosis, Wenzhou Central Hospital, Wenzhou, 325000, People's Republic of China. wzxxq@139.com.
Abstract
BACKGROUND: The phenotypes of uniparental disomy (UPD) are variable, which may either have no clinical impact, lead to clinical signs and symptoms. Molecular analysis is essential for making a correct diagnosis. This study involved a retrospective analysis of 4512 prenatal diagnosis samples and explored the molecular characteristics and prenatal phenotypes of UPD using a single nucleotide polymorphism (SNP) array. RESULTS: Out of the 4512 samples, a total of seven cases of UPD were detected with an overall frequency of 0.16%. Among the seven cases of UPD, two cases are associated with chromosomal aberrations (2/7), four cases (4/7) had abnormal ultrasonographic findings. One case presented with iso-UPD (14), and two case presented with mixed hetero/iso-UPD (15), which were confirmed by Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) as maternal UPD (15) associated with Prader-Willi syndrome (PWS). Four cases had iso-UPD for chromosome 1, 3, 14, and 16, respectively; this is consistent with the monosomy rescue mechanism. Another three cases presented with mixed hetero/isodisomy were consistent with a trisomy rescue mechanism. CONCLUSION: The prenatal phenotypes of UPD are variable and molecular analysis is essential for making a correct diagnosis and genetic counselling of UPD. The SNP array is a useful genetic test in prenatal diagnosis cases with UPD.
BACKGROUND: The phenotypes of uniparental disomy (UPD) are variable, which may either have no clinical impact, lead to clinical signs and symptoms. Molecular analysis is essential for making a correct diagnosis. This study involved a retrospective analysis of 4512 prenatal diagnosis samples and explored the molecular characteristics and prenatal phenotypes of UPD using a single nucleotide polymorphism (SNP) array. RESULTS: Out of the 4512 samples, a total of seven cases of UPD were detected with an overall frequency of 0.16%. Among the seven cases of UPD, two cases are associated with chromosomal aberrations (2/7), four cases (4/7) had abnormal ultrasonographic findings. One case presented with iso-UPD (14), and two case presented with mixed hetero/iso-UPD (15), which were confirmed by Methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) as maternal UPD (15) associated with Prader-Willi syndrome (PWS). Four cases had iso-UPD for chromosome 1, 3, 14, and 16, respectively; this is consistent with the monosomy rescue mechanism. Another three cases presented with mixed hetero/isodisomy were consistent with a trisomy rescue mechanism. CONCLUSION: The prenatal phenotypes of UPD are variable and molecular analysis is essential for making a correct diagnosis and genetic counselling of UPD. The SNP array is a useful genetic test in prenatal diagnosis cases with UPD.
Entities:
Keywords:
prenatal diagnosis; single nucleotide polymorphism array; uniparental disomy
Authors: D L Bruno; S M White; D Ganesamoorthy; T Burgess; K Butler; S Corrie; D Francis; L Hills; K Prabhakara; C Ngo; F Norris; R Oertel; M D Pertile; Z Stark; D J Amor; H R Slater Journal: J Med Genet Date: 2011-10-29 Impact factor: 6.318
Authors: Laura K Conlin; Brian D Thiel; Carsten G Bonnemann; Livija Medne; Linda M Ernst; Elaine H Zackai; Matthew A Deardorff; Ian D Krantz; Hakon Hakonarson; Nancy B Spinner Journal: Hum Mol Genet Date: 2010-01-06 Impact factor: 6.150