Single Nucleotide Polymorphisms (SNP) are the most common and simplest form of variation associated with genetic diseases. SNPs are responsible for more than half of the genetic polymorphisms known to cause inherited diseases. The SNPs are single base changes in the DNA sequence which are responsible for genetic diversity among individuals to the occurrence of diseases. The identification and analysis of the effects of SNP in relation to diseases can be helpful in early detection of diseases, preventing the onset of diseases, reducing the ill effects of diseases and in personalized drug development. The paper focuses on the method of detection of SNPs and associated disease genes using the National Center for Biotechnology Information (NCBI) resources. The BLAST, NCBI Map Viewer, dbSNP and Cn3D tools have been used to identify the SNPs and associated genes aligning the given Expressed Sequence Tag (EST). The results show the presence of a SNP in the used EST. The SNP is responsible for Hemochromatosis disease caused by variation in the HFE gene. The method can be generalized and used to identify the SNPs and disease genes present in a given DNA sequence.