Sykes B, Francis M J, Smith R
N Engl J Med. 1977 May 26;296(21):1200-3. doi: 10.1056/NEJM197705262962104.
To ascertain if the features of osteogenesis imperfecta could be due to an abnormality in two genetically distinct collagens, Type III and Type I, we measured, in pepsin digests of skin, the ratio of the alpha 1, (III) to alpha 1 (I) chains derived from the two types, using a method of interrupted polyacrylamide-gel electrophoresis. In 40 control subjects this ratio decreased from about 0.45 in early fetal life to a mean (+/-2 S.D.) of 0.14 +/- 0.06 in 14 adults. Seven of nine adult patients with mild osteogenesis imperfecta had ratios of more than 4 S.D., above this mean, as did two of five patients with severe osteogenesis imperfecta. The increased ratio was probably due to a reduction of Type I collagen. If this reduction were generalized it could contribute to the bony fragility of osteogenesis imperfecta, since mineralized bone contains Type I collagen only.
为了确定成骨不全的特征是否可能归因于两种基因上不同的胶原蛋白（III型和I型）的异常，我们使用间断聚丙烯酰胺凝胶电泳法，在皮肤的胃蛋白酶消化物中测量了源自这两种类型的α1(III)链与α1(I)链的比例。在40名对照受试者中，该比例从胎儿早期的约0.45降至14名成年人中的平均（±2标准差）0.14±0.06。9名轻度成骨不全的成年患者中有7名的比例超过该平均值4个标准差以上，5名重度成骨不全患者中有2名也是如此。该比例增加可能是由于I型胶原蛋白减少所致。如果这种减少是全身性的，那么它可能导致成骨不全患者的骨质脆弱，因为矿化骨仅含I型胶原蛋白。
