Objective: To discuss the implications of expanded genetic carrier screening for preconception purposes based on our practice.
Methods: One hundred and forty-three potential gamete donors aged 20-32 years old (µ=24, 127 females and 16 males), signed informed consent forms and were selected according to the REDLARA guidelines. Blood or saliva samples were examined by one of these genetic carrier screening methods: Genzyme screening for Cystic Fibrosis (CF), Fragile X and Spinal Muscular Atrophy (SMA); Counsyl Universal panel or Recombine Carrier Map.
Results: Genotyping results for all donors were analyzed; 41% (58/143) of donors were identified as carriers for at least one condition. We found a carrier frequency of 1/24 for CF, 1/72 for SMA and 0/120 for Fragile X syndrome. Among the high-impact most prevalent conditions in our study (Carrier Map group) were: 21-Hydroxilase-Deficient Congenital Nonclassical Adrenal Hyperplasia (1/8), Factor V deficiency (1/12), Hemochromatosis: Type 1: HFE Related (1/12), Short Chain Acyl-CoA (1/14) and MTHFR deficiency 1/3 (39%).
Conclusions: The rate of gamete donors identified as carriers of at least one condition was 41%, which supports the offering of expanded carrier screening to our population. Studies in Latin American populations could help customize screening panels. The ART patient population has a unique opportunity to be offered expanded carrier screening and appropriate counseling, to make its best-informed decisions.
Keywords: CF; Expanded carrier screening; SMA.