Findings from ACGH in patient with psychomotor delay-case report

Abstract

Initial testing of children with psychomotor delays considers karyotype analysis and metabolic tests. However, introduction of Array Comparative Genomic Hybridization (ACGH) has become the standard method of diagnostics worldwide. ACGH is a highly sensitive method which enables detection of unbalanced chromosomal aberrations and aneuploidies. In this case report, a patient is a sixteen year old girl born to unrelated parents with mild mental retardation and psychomotor delay, hyperacusis, epilepsy, silent nasal speech, clinodactyly of the V finger on left hand, as well as low set ears. Patient had a karyotype interpreted as normal using GTG band analysis. Array CGH was performed using Agilent SurePrint G3 custom CGH+SNP Microarray 8x60K (UCSC, hg19, NCBI Build 37, February,2009). Results were analyzed by CytoGenomics 3.0 Agilent software. Results of aCGH revealed clinically significant duplication of 17q25.1-q25.3 region with the size of~7.96Mb. Within the duplicated region 217 genes are present, of which 36 are described as OMIM morbid. Duplications of similar size are described in DECIPHER date base in patients with psychomotor delay, hyperactivity and neoplasm of CNS. Besides duplication, a ~755kb clinically significant deletion was detected in the 17q25.3 region. Deletion involves 18 genes of which 2 are described as OMIM morbid: TBCD (MIM604649) and ZNF750 (MIM610226). Patient with similar deletion was described in DECIPHER date base with notable psychomotor delay. Based on these results FISH analysis is recommended for both parents in order to determine the possible carrier of inversion in the region of 17qter.

Keywords

• Array Comparative Genomic Hybridization
• deletion
• duplication