BlueCross BlueShield of Tennessee Medical Policy Manual

Genetic Testing for CHARGE Syndrome

DESCRIPTION

CHARGE syndrome is a rare genetic condition associated with multiple congenital anomalies. The letters of CHARGE syndrome correspond to clinical features: C = ocular Coloboma, H = Heart defect, A = Atresia choanae, R = Retarded growth and development, G = Genital hypoplasia and E = Ear anomalies/deafness. There are other malformations also common in this condition. In particular, hypoplasia of the semi-circular canals has emerged as a frequent and distinctive CHARGE malformation. The condition is caused by mutations of the CHD7 gene on chromosome 8q12.1. CHD7 is the only gene currently known to be associated with CHARGE syndrome.

In many individuals, the diagnosis can be made based on clinical findings. Since the phenotype of the disease is highly variable, some individuals do not fulfill all the criteria for diagnosis by clinical findings. Major characteristics include ocular coloboma, choanal atresia or stenosis, cranial nerve abnormality, ear anomalies or deafness. Minor characteristics include genital hypoplasia, hypogonadotrophic hypogonadism, developmental delays, cardiac malformations, short stature, cleft lip and/or cleft palate, tracheoesophageal fistula, and distinctive CHARGE facial appearance, which consist of a prominent forehead and a prominent nasal bridge. Other, less frequent manifestations include kidney malformations, immunodeficiency, various limb abnormalities, scoliosis, dental problems, omphalocele, brain malformations, attention deficit hyperactivity disorder (ADHD), and various behavioral problems.

Most instances of CHARGE syndrome are sporadic events in a family and appear to be caused by de novo CHD7 mutations, but on rare occasions CHARGE can be inherited as an autosomal dominant condition. Recurrence in siblings because of germline mosaicism has also been reported. The prevalence of CHARGE syndrome is estimated at 1 in 8,500 live births.

POLICY

MEDICAL APPROPRIATENESS

IMPORTANT REMINDERS

ADDITIONAL INFORMATION  

A diagnosis of definite CHARGE syndrome can be made clinically in individuals with all four major characteristics or three major and three minor characteristics. In individuals without the classical clinical criteria to diagnose CHARGE, in those with a milder phenotype, and/or in those with features that overlap with and cannot be distinguished from other syndromes, genetic testing may provide a definitive diagnosis.

SOURCES

BlueCross BlueShield Association. Evidence Positioning System. (3:2024). Genetic testing for CHARGE syndrome (2.04.106). Retrieved September 13, 2024 from www.bcbsaoca.com/eps/. (19 articles and/or guidelines reviewed)

Legendre, M., Abadie, V., Attié-Bitach, T., Philip, N., Busa, T., Bonneau, D., et al. (2017) Phenotype and genotype analysis of a French cohort of 119 patients with CHARGE syndrome. American Journal of Medical Genetics, 175 (4), 417–430. (Level 3 evidence)

Thomas, A. T., Waite, J., Williams, C. A., Kirk, J., Oliver, C., & Richards, C. (2022). Phenotypic characteristics and variability in CHARGE syndrome: a PRISMA compliant systematic review and meta-analysis. Journal of Neurodevelopmental Disorders, 14 (1), 49. (Level 1 evidence)

van Ravenswaaij-Arts, C.M., Blake, K., Hoefsloot, L., & Verloes, A. (2015). Clinical utility gene card for: CHARGE syndrome - update 2015. European Journal of Human Genetics, 23 (11), doi:10.1038/ejhg.2015.15 (Level 2 evidence)

ORIGINAL EFFECTIVE DATE:  2/9/2014

MOST RECENT REVIEW DATE:  10/10/2024

ID_BA

Policies included in the Medical Policy Manual are not intended to certify coverage availability. They are medical determinations about a particular technology, service, drug, etc. While a policy or technology may be medically necessary, it could be excluded in a member's benefit plan. Please check with the appropriate claims department to determine if the service in question is a covered service under a particular benefit plan. Use of the Medical Policy Manual is not intended to replace independent medical judgment for treatment of individuals. The content on this Web site is not intended to be a substitute for professional medical advice in any way. Always seek the advice of your physician or other qualified health care provider if you have questions regarding a medical condition or treatment.

This document has been classified as public information.