Orofacial cleft (OFC) is a prevalent birth defect, occurring in approximately 1 out of every 600 newborns. This condition can manifest as a cleft lip, a combination of a cleft lip and palate, or a cleft palate alone. Around 6% of all children diagnosed with OFC have a chromosomal cause. Studies focusing on newborns with clefts frequently report chromosomal disorders like trisomies 18 and 13, which typically result in a limited lifespan, rarely exceeding a year. 

Older children with a cleft, developmental delay (DD), and minor physical anomalies are often seen in craniofacial clinics. However, a chromosomal cause in these children may not be immediately recognized during infancy due to its subtle presentation. Chromosomal microarray (CMA), a technique used to identify chromosomal variations, is the primary diagnostic tool for children with congenital anomalies, DD, and intellectual disability. 

Children who have both DD and craniofacial defects bear a significantly higher risk of genomic rearrangements compared to children who have DD coupled with autism or seizures. With the help of array-based methods, researchers have been able to identify potential chromosomal locations in children with both a cleft lip and palate.

Reference:
1. Shenoy RD, Shenoy V, Shetty V. Chromosomal Abnormalities in Syndromic Orofacial Clefts: Report of Three Children. Case Rep Genet. 2018 Sep 9;2018:1928918. doi: 10.1155/2018/1928918. PMID: 30271639; PMCID: PMC6151207.