Table 1.

SMA deletion and likely silent AJ carriers identified. Screening results from SMN1 copy number and g.27134T > G genotyping analyses are shown for the AJ (Ashkenazi Jewish) subcohort. Carrier frequencies for the likely silent carriers may be underestimates, since some are missed even with g.27134T > G genotyping (Luo et al., 2014). Residual risk estimates are noted in the text and were calculated as per (Luo et al., 2014)

Category	Copy number and genotyping results	n	1 in
1 (deletion carriers)	SMN1 copies = 1, g.27134T>G: Negative	64	76
2	SMN1 copies = 2, g.27134T>G: Negative	4,094
3 (likely silent carriers)	SMN1 copies = 2, g.27134T>G: Positive	17	285
4	SMN1 copies≥=3, g.27134T>G: Negative	365
5	SMN1 copies≥=3, g.27134T>G: Positive	302
Total tested		4,842