Letter: Serum alpha-fetoprotein in cystic fibrosis.

Professor R. K. Chandra and others suggest that estimation of serum alpha-fetoprotein 
(AFP) might help in detecting carriers in families at risk for 
cystic fibrosis. Observers in the U.K. have been unable to confirm 
these findings, whereas Dr. J. A. Smith of New York supports 
them. Perhaps the crux of the matter lies in the technique 
of estimating serum AFP. if a small number of families is 
analysed the proportion of affected individuals may differ from the expected. 
By chance some families may have all normal children whereas some 
may have all affected children. For example, nowadays, since families tend 
to be small, the appearance of an autosomal recessive condition is 
often sporadic with only one affected person in the family. This 
could well apply to cystic fibrosis. 