6q13q14.3 Microdeletion Syndrome with Severe Hypotonia and Facial Dysmorphism: Genotype–Phenotype Correlation

Abstract

Hypotonia is a symptom of diminished tone of skeletal muscle and can be nongenetic or a part of genetic syndrome. Hypotonia, developmental delay, and facial dysmorphism are nonspecific findings observed in many genetic syndromes mostly in chromosomal microdeletion and duplication. Here we report a case with severe hypotonia and facial dysmorphism, diagnosed with deletion at 6q13q14.3 by array comparative genomic hybridization (CGH) at very early age. Recent genetic diagnostic technologies such as array CGH may enable clinicians to diagnose chromosomal abnormalities earlier and provide appropriate medical management

Keywords

array CGH - 6q deletion - hypotonia

• References

• 1 Peredo DE, Hannibal MC. The floppy infant: evaluation of hypotonia. Pediatr Rev 2009; 30 (09) e66-e76
• 2 Lisi EC, Cohn RD. Genetic evaluation of the pediatric patient with hypotonia: perspective from a hypotonia specialty clinic and review of the literature. Dev Med Child Neurol 2011; 53 (07) 586-599
• 3 Xu J, Chen Z. Advances in molecular cytogenetics for the evaluation of mental retardation. Am J Med Genet C Semin Med Genet 2003; 117C (01) 15-24
• 4 Engwerda A, Frentz B, den Ouden AL. et al. The phenotypic spectrum of proximal 6q deletions based on a large cohort derived from social media and literature reports. Eur J Hum Genet 2018; 26 (10) 1478-1489
• 5 Catena S, Aracena M, Pizarro Ó, Espinoza K, Lay-Son G. Proximal deletion of 6q overlapping with Toriello-Carey facial phenotype: prenatal findings, clinical course, differential diagnosis, and review. Mol Syndromol 2017; 9 (01) 15-21
• 6 Van Esch H, Rosser EM, Janssens S, Van Ingelghem I, Loeys B, Menten B. Developmental delay and connective tissue disorder in four patients sharing a common microdeletion at 6q13-14. J Med Genet 2010; 47 (10) 717-720
• 7 Toriello HV, Carey JC, Addor MC. et al. Toriello-Carey syndrome: delineation and review. Am J Med Genet A 2003; 123A (01) 84-90
• 8 Toriello HV, Hatchwell E. Toriello-Carey syndrome phenotype and chromosome anomalies. Am J Med Genet A 2008; 146A (01) 116
• 9 Punetha J, Kesari A, Hoffman EP. et al. Novel Col12A1 variant expands the clinical picture of congenital myopathies with extracellular matrix defects. Muscle Nerve 2017; 55 (02) 277-281
• 10 Ma L, Li J, Liu Y, Pang S, Huang W, Yan B. Novel and functional variants within the TBX18 gene promoter in ventricular septal defects. Mol Cell Biochem 2013; 382 (1-2): 121-126
• 11 Cai CL, Martin JC, Sun Y. et al. A myocardial lineage derives from Tbx18 epicardial cells. Nature 2008; 454 (7200): 104-108
• 12 de Ligt J, Willemsen MH, van Bon BW. et al. Diagnostic exome sequencing in persons with severe intellectual disability. N Engl J Med 2012; 367 (20) 1921-1929
• 13 Drago A, Alboni S, Brunello N, De Ronchi D, Serretti A. HTR1B as a risk profile maker in psychiatric disorders: a review through motivation and memory. Eur J Clin Pharmacol 2010; 66 (01) 5-27