of many genomic loci flanked by Alu repetitive elements, which are non-autonomous retrotransposons present in high number of copies in primate genomes. Alu element can be used for genome fingerprinting based on PCR, which is also called Alu PCR. Transposon-tagged sequences There are several ways to analyze the function of a particular gene sequence, the most direct method is to replace it or cause a mutation and then to analyze the results and effects. There are three method are developed for this purpose: gene replacement, sense and anti-sense suppression, and insertional mutagenesis. Among these methods, insertional mutagenesis was proved to be very good and successful approach. At first, T-DNA was applied for insertional mutagenesis. However, using transposable element can bring more advantages. Transposable elements were first discovered by Barbara McClintock in maize plants. She identified the first transposable genetic element, which she called the Dissociation (Ds) locus. The size of transposable element is between 750 and 40000bp. Transposable element can be mainly classified as two classes: One class is very simple, called insertion sequence (IS), the other class is complicated, called transposon. Transposon has one or several characterized genes, which can be easily identified. IS has the gene of transposase. Transposon can be used as tag for a DNA with a know sequence. Transposon can appear at other locus through transcription or reverse transcription by the effect of nuclease. This appearance of transposon proved that genome is not statistical, but always changing the structure of itself. There are two advantages by using transposon tagging. First, if a transposon is inserted into a gene sequence, this insertion is single and intact. The intactness can make tagged sequence easily to molecular analysis. The other advantage is that, many transposons can be found eliminated from tagged gene sequence when transposase is analyzed. This provides confirmation that the inserted gene sequence was really tagged by transposon. Example of GSS file The following is an example of GSS file that can be submitted to GenBank: TYPE: GSS STATUS: New CONT_NAME: Sikela JM GSS#: Ayh00001 CLONE: HHC189 SOURCE: ATCC SOURCE_INHOST: 65128 OTHER_GSS: GSS00093, GSS000101 CITATION: Genomic sequences from Human brain tissue SEQ_PRIMER: M13 Forward P_END: 5' HIQUAL_START: 1 HIQUAL_STOP: 285 DNA_TYPE: Genomic CLASS: shotgun LIBRARY: Hippocampus, Stratagene (cat. #936205) PUBLIC: PUT_ID: Actin, gamma, skeletal COMMENT: SEQUENCE: AATCAGCCTGCAAGCAAAAGATAGGAATATTCACCTACAGTGGGCACCTCCTTAAGAAGCTG ATAGCTTGTTACACAGTAATTAGATTGAAGATAATGGACACGAAACATATTCCGGGATTAAA CATTCTTGTCAAGAAAGGGGGAGAGAAGTCTGTTGTGCAAGTTTCAAAGAAAAAGGGTACCA GCAAAAGTGATAATGATTTGAGGATTTCTGTCTCTAATTGGAGGATGATTCTCATGTAAGGT GCAAAAGTGATAATGATTTGAGGATTTCTGTCTCTAATTGGAGGATGATTCTCATGTAAGGT TGTTAGGAAATGGCAAAGTATTGATGATTGTGTGCTATGTGATTGGTGCTAGATACTTTAAC TGAGTATACGAGTGAAATACTTGAGACTCGTGTCACTT || References Bioinformatics Genomics