CONTIGUOUS DELETION AND DUPLICATION MUTATIONS RESULTING IN TYPE-1 HEREDITARY ANGIONEUROTIC-EDEMA

Mutations that cause low antigenic and functional levels of C1 inhibit or protein result in type 1 hereditary angioneurotic edema. This disea se is characterized by episodic edema leading to considerable morbidit y and sometimes death. We present here two novel mutations in the reac tive center coding region. One mutation is a deletion of an imperfect palindrome encompassing nucleotides 1395-1428 and the other is a direc t duplication of nucleotides 1414-1433. These mutations do not depend on improper pairing of direct repeats, but may form as a consequence o f a peculiar consensus sequence or an alternative secondary structure.