Open Access

Fátima Gimeno-Ferrer, David Albuquerque, Maria Capataz Ledesma, Carolina Monzó, Guillermo Gervasini, Francisco Barros Angueira, José María Carbonell, Goitzane Marcaida Benito, Raquel Rodríguez-López, Enrique Galán Gómez

• Since genomic SNPs/CNVs arrays were implemented as a diagnostic tool in clinical settings to search for the cause of idiopathic intellectual disability, chromosomal imbalances have been precisely described as being the cause of many new syndromes, especially when they are associated with multiple congenital anomalies and/or dimorphism. High-density SNPs/CNVs microarray was used to delineate genotype-phenotype correlation in a 2.5 year-old girl who carried a mosaic characterized by a predominant cell line representing 92% which carried a duplication of 12.5 Mb of the 18p11.32p11.21 chromosomal region (chr18:12602631_telomeric) and a deletion and a deletion of 20.3 Mb of the 18q21.32q23 chromosomal region (chr18:57691236_telomeric) and a second minor cell line (8%) presented a ring chromosome, carrying the deletion of 20.3 Mb of the 18q21.32q23 chromosomal region. The microarray analysis identified the genetic causes for the specific phenotype of the patient, whose more evident signs andSince genomic SNPs/CNVs arrays were implemented as a diagnostic tool in clinical settings to search for the cause of idiopathic intellectual disability, chromosomal imbalances have been precisely described as being the cause of many new syndromes, especially when they are associated with multiple congenital anomalies and/or dimorphism. High-density SNPs/CNVs microarray was used to delineate genotype-phenotype correlation in a 2.5 year-old girl who carried a mosaic characterized by a predominant cell line representing 92% which carried a duplication of 12.5 Mb of the 18p11.32p11.21 chromosomal region (chr18:12602631_telomeric) and a deletion and a deletion of 20.3 Mb of the 18q21.32q23 chromosomal region (chr18:57691236_telomeric) and a second minor cell line (8%) presented a ring chromosome, carrying the deletion of 20.3 Mb of the 18q21.32q23 chromosomal region. The microarray analysis identified the genetic causes for the specific phenotype of the patient, whose more evident signs and symptoms were mainly associated to the genomic regions duplicated and in haploinsufficiency. Although the conventional karyotype is currently considered a diagnostic technique of support or second line, it was key to establish the etiology of the alteration that the patient carried. Its performance allowed the correct interpretation of the result of the array, whose characterization facilitated its correlation with the phenotypic features of the patient. From both tests, it was possible to conclude the existence of ring chromosome 18, as well as the percentage of the mosaic lines. The deleterious capabilities of the affected OMIM and dominant genes were evaluated along her period of life. A rigorous clinical following up in that patient included valorous phenotypic data to the array data bases, and will make less difficult to hypothesize about prognosis in other individuals who carry overlapping similar high risk genetic alterations.…