Table 1. Age and DMD mutations.

Asterisks mark subject in whom mutation analysis from an affected brother was accepted. Implications of reading frame are discussed in the text. The last two columns describe predicted effect of the mutation on expression of other relevant DMD isoforms by deletion of either the appropriate promoter/exon 1 or by downstream domains. * Indicates those followed at both 6 and 12 months.

#	Age (mos)	Family History	Mutation	Exon(s)	Frame	Disruption of Dp140 isoform	Disruption of Dp71 isoform
1*	4.4	Yes	Deletion	3–32	In	No	No
2*	4.9	No	Deletion	3–41	In	No	No
3*	7.6	Yes	Deletion	45	Out	Yes	No
4*	14.6	Yes	Duplication	2	Out	No	No
5*	14.8	Yes	Deletion	45–50	Out	Yes	No
6*	17.0	Yes	Deletion	46–50	Out	Yes	No
7*	20.6	Yes	Deletion*	46	Out	Yes	No
8*	21.7	Yes	Deletion	45–50	Out	Yes	Yes
9	26.5	Yes	Nonsense (c.2353C>T; p.Gln785X)	19	Out	No	No
10*	26.9	No	Deletion	51–57	Out	Yes	Yes
11*	28.9	No	Deletion	53–55	Out	Yes	No
12	28.9	No	Deletion	45	Out	Yes	No
13*	29.2	No	Deletion	49–52	Out	Yes	No
14*	29.3	No	Deletion	58–64	Out	Yes	Yes
15	31.3	Yes	Deletion	18–25	In	Yes	No
16	32.5	No	Deletion	46–52	Out	Yes	No
17	33.6	No	Nonsense (c.2791G>T; p.Glu931X)	21	Out	No	No
18	33.8	No	Deletion	45	Out	Yes	No
19	34.2	Yes	Deletion	12–44	Out	Unknown	No