HIws1 is an 819 amino acid nuclear protein that contains one TFIIS N-terminal domain. Belonging to the IWS1 family, hIws1 exists as three alternatively spliced isoforms, which are encoded by a gene mapping to human chromosome 2q14.3. Chromosome 2 is the second largest human chromosome, consisting of 237 million bases, encoding over 1,400 genes and making up approximately 8% of the human genome. A number of genetic diseases are linked to genes on chromosome 2. Harlequin icthyosis, a rare and morbid skin deformity, is associated with mutations in the ABCA12 gene. The lipid metabolic disorder sitosterolemia is associated with ABCG5 and ABCG8. An extremely rare recessive genetic disorder, Alstr鰉 syndrome, is due to mutations in the ALMS1 gene. Interestingly, chromosome 2 contains what appears to be a vestigial second centromere and vestigial telomeres which gives credence to the hypothesis that human chromosome 2 is the result of an ancient fusion of two ancestral chromosomes seen in modern form today in apes