FLG loss of Function Mutations R501X and R2447X in Puerto Rico: Association to Atopic Dermatitis and Ichtyosis Vulgaris Conference Poster uri icon


  • In Puerto Rico we do not have many studies of Loss of function (LoF) mutations; but using the data from the 1000 Genome Project (1KGP) we identified several polymorphisms that predicted to eliminate protein function. In this research, we work with two single nucleotide polymorphisms (SNPs) that produce premature stop codons in the FLG gene. They are known as R501X and R2447X. Both are associated to skin conditions such as ichthyosis vulgaris and atopic dermatitis; they also have been associated to asthma and some type of allergies. The 1KGP data is based on the analysis of 104 Puerto Ricans only, and we wanted to test if the frequencies in it were accurate. We genotyped 691 individuals for the mutation R501X and 292 for R2447X using real time PCR. From the 691 individuals, we found 21 heterozygotes for the SNP R501X, this mutation in the FLG gene having an allele frequency of 0.0152. This allele frequency compared to the one reported in the 1KGP, shows a difference of 0.01039 suggesting that the mutation in Puerto Rico is not rare. This mutation has been identified mainly in 3 geographical regions of Puerto Rico with higher European heritage. We started working with the mutation R2447X and genotyped 292 individuals, and 3 heterozygotes were found. This mutation shows an allelic frequency of 0.002, but the 1KGP have a higher allelic frequency (0.005). Now, we expect to genotype the same individuals for both mutations and compare their distribution, prevalence and relation between both.

publication date

  • May 4, 2019