Frequent detection of parental consanguinity in children with developmental disorders by a combined CGH and SNP microarray
1 Department of Pathology and Mailman Center for Child Development, Room 7050, University of Miami Miller School of Medicine, 1601 NW 12th Avenue, Miami, FL 33136, USA
2 Department of Human Genetics, University of Miami Miller School of Medicine, Miami, FL, USA
3 Memorial Regional Hospitals, Miami, FL, USA
4 Jackson Memorial Hospital, Hollywood, FL, USA
5 Núcleo de Genética Médica, Belo Horizonte, Belo Horizonte, MG, Brazil
Molecular Cytogenetics 2013, 6:38 doi:10.1186/1755-8166-6-38Published: 20 September 2013
Genomic microarrays have been used as the first-tier cytogenetic diagnostic test for patients with developmental delay/intellectual disability, autism spectrum disorders and/or multiple congenital anomalies. The use of SNP arrays has revealed regions of homozygosity in the genome which can lead to identification of uniparental disomy and parental consanguinity in addition to copy number variations. Consanguinity is associated with an increased risk of birth defects and autosomal recessive disorders. However, the frequency of parental consanguinity in children with developmental disabilities is unknown, and consanguineous couples may not be identified during doctor’s visit or genetic counseling without microarray.
We studied 607 proband pediatric patients referred for developmental disorders using a 4 × 180 K array containing both CGH and SNP probes. Using 720, 360, 180, and 90 Mb as the expected sizes of homozygosity for an estimated coefficient of inbreeding (F) 1/4, 1/8, 1/16, 1/32, parental consanguinity was detected in 21cases (3.46%).
Parental consanguinity is not uncommon in children with developmental problems in our study population, and can be identified by use of a combined CGH and SNP chromosome microarray. Identification of parental consanguinity in such cases can be important for further diagnostic testing.