Gonosomal mosaicism for an NF1 deletion in a sperm donor: evidence of the need for coordinated, long-term communication of health information among relevant parties

Screening of gamete donors can reduce but cannot eliminate the risks for medical problems in donor-conceived offspring. We present a case of gonosomal mosaicism discovered in an anonymous sperm donor after receiving two reports of neurofibromatosis type 1 (NF1) in donor-conceived offspring, to illustrate that long-term, systematic investigation of health issues in donors and offspring can be invaluable to the welfare of these individuals.