An Algerian child homozygous for the M470V polymorphism and for a deletion of two nucleotides in exon 10 of the CFTR gene, shows severe cystic fibrosis symptoms.

When screening for the presence of major cystic fibrosis mutations in Algerian cystic fibrosis families by heteroduplex formation, aberrant heteroduplexes were observed for exon 10 in one family. Here we describe the clinical and molecular findings in a severely affected child of this family, homozygous for the 1609delCA and for the M470V polymorphism.