Carrier testing is primarily useful in the reproductive period to determine the risk of an individual having a child affected by the condition for which testing is being considered. Knowing that a child is a carrier of an X-linked or autosomal recessive condition usually does not alter medical care in the pediatric years since most carriers are unaffected. Thus, in most situations, there is not a medical indication for carrier testing in a child. Undertaking carrier testing of a child violates the right of the child to make his or her own decision about testing and could potentially impair future insurability. An exception could be made for a mature adolescent who may be able to understand the reproductive implications of carrier testing after appropriate genetic counselling.
Sources:
Borry P, et al. Carrier testing in minors: a systematic review of guidelines and position papers. Eur J Hum Genet. 2006 Feb;14(2):133-8. PMID: 16267502.
Committee on Bioethics, American College of Medical Genetics, et al. Ethical and policy issues in genetic testing and screening of children. Pediatrics. 2013 Mar;131(3):620-2. PMID: 23428972.
Guidelines for genetic testing of healthy children. Paediatr Child Health. 2003 Jan;8(1):42-52. PMID: 20011555.