TANDEM-REPEAT INTERNAL MAPPING (TRIM) OF THE INVOLUCRIN GENE - REPEATNUMBER AND REPEAT-PATTERN POLYMORPHISM WITHIN A CODING REGION IN HUMAN-POPULATIONS

We have analyzed the human involucrin gene in 41 British African-Carib beans and 37 British white Caucasians by tandem-repeat internal mappin g and DNA sequencing. A point mutation (i.e., B(c)) in the last B repe at unit was found in 98.6% of British white Caucasians and in 52.4% of British African-Caribbeans. The distribution of repeat patterns was a lso different between the two populations. Nine previously unreported repeat pattern alleles, 4 with and 5 without the B(c) repeat, have bee n found, increasing the range of variation in humans to 15 reported re peat patterns, 6 with and 9 without the Caucasian mutation. Three furt her sequence variations, each occurring in a single individual, were f ound. The evolutionary significance of variation in the human involucr in gene is discussed.