Table 1.

Characteristics of de novo and inherited OI cases

All patients	de novo	%	Inherited	%	Total	%	p‐value
Total	82	56.16	64	43.84	146	100
EE	10	37.04	17	62.96	27	18.49
UA	36	58.06	26	41.93	62	42.47
VN	36	63.16	21	36.84	57	39.04
Sex
Males	34	49.28	35	50.72	69	47.26	0.1338
Females	48	62.34	29	37.66	77	52.74
OI type
OI1	22 (26.83%)	43.14	29 (45.31%)	56.86	51	34.93	0.0002
OI2	1 (1.22%)	100.00	0	0.00	1	0.69
OI3	29 (35.36%)	85.29	5 (7.81%)	14.71	34	23.29
OI4	30 (36.59%)	50.00	30 (46.88%)	50.00	60	41.09
Fractures
Number of total fractures (mean)	21.96		12.50		17.81		0.0224
Fractures per year (mean)	1.74		1.07		1.45		0.0014
Genotype
COL1A1 a	58 (65.91%)	52.25	53 (81.54%)	47.75	111	72.55	0.0360
COL1A2 b	30 (34.09%)	71.43	12 (18.46%)	28.57	42	27.45
Functional type
Loss of function	28 (31.82%)	43.75	36 (55.38%)	56.25	64	41.83	0.0063
Nonsense and frameshift	12	37.50	20	62.50	32
Splice site	16	50.00	16	50.00	32
Missense	60 (68.18%)	67.42	29 (44.62%)	32.58	89	58.17
Gly	48	68.57	22	28.57	70		0.0139
Gly‐Ser	24	61.54	15	38.46	39		0.5796
Architecture of mutations
Transitions	54	56.84	41	43.16	95	62.09	0.6039
Transversions	24	63.16	14	36.84	38	24.84
Indel	10	50.00	10	50.00	20	13.07

Significant p‐values marked in bold.

^a COL1A1 GenBank reference sequence (gDNA NG_007400.1, cDNA NM_000088.3).

^b COL1A2 GenBank reference sequence (gDNA NG_007405.1, cDNA NM_000089.3).