The alpha 1-antitrypsin gene and its deficiency states

alpha 1-antitrypsin, a 52 kDa antiprotease, provides the major defense to the lower respiratory tract against the ravages of neutrophil elastase, a powerful serine protease. A variety of mutations in the coding exons of the alpha 1-antitrypsin gene result in 'alpha 1-antitrypsin deficiency', leading to emphysema at an early age. A subset of mutations cause liver disease and a rare mutation is associated with a bleeding diathesis. Preventive treatment for the emphysema associated with alpha 1-antitrypsin deficiency is available in the form of intermittent infusions with alpha 1-antitrypsin, and strategies have been developed to reverse the deficiency state with gene therapy.     

Cardiac conduction disorders in six infants with "near-miss" sudden infant deaths.

Cardiac conduction disorders caused sudden serious illnesses in six infants that might have been fatal if diagnosis and treatment had been delayed. These cases provide circumstantial evidence to support a link between cardiac conduction disorders and some sudden infant deaths. A further potential long-term effect of these disorders is illustrated in one child in whom psychomotor retardation seemed to develop after an episode of cerebral hypoxia that was probably by an arrhythmia associated with the Wolff-Parkinson-White syndrome. Cardiac conduction disorders may be detected by routine neonatal ECG screening, and it may therefore be appropriate to start prophylactic antiarrhythmic treatment in certain children before clinical signs develop.     

Procollagen alpha2 mRNA is significantly different from procollagen alpha1(I) mRNA in size or secondary structure.

The fractionation of fetal calf tendon messenger RNA in 85 percent formamide sucrose gradients shows a separation of the mRNAs coding for pro α1(I) and pro α2 chains of type I collagen. This difference in sedimentation in denaturing gradients suggests that pro α2 mRNA is approxmately 1000 bases shorter than pro α1(I) mRNA. However, such a size difference is significantly greater than would be predicted from consideration of the size of the polypeptide chains coded for by these mRNAs, and thus, residual secondary structure in the mRNAs may contribute to these apparent size differences.