With the publication of the sequence of human chromosome 5, there is fresh recognition that junk DNA is not junk but has "a powerful regulatory influence". Thought some of you might be interested in the following. I remember a few years ago, for instance, when Galatian under one of his other names and I were on another forum and he was propunding about how junk DNA was a powerful evidence for evolution... ---------- Human genome hits halfway mark BBC News, Wednesday, 15 September, 2004 http://news.bbc.co.uk/1/hi/sci/tech/3658386.stm Extract on Junk DNA: It is not just the genes in chromosome five that the scientists are interested in. Volumes of genetic material lie in between the genes, which for a long time were dismissed as "junk" by researchers. But on closer inspection, it seems this judgement was premature. The fact that sequences of junk were conserved for hundreds of generations suggests they have a function worth holding on to. "Important genetic motifs gleaned from vast stretches of non-coding sequence have been found on chromosome five," said Eddy Rubin, JGI's director. "Comparative studies conducted by our scientists of the vast gene desert... have shown these regions, conserved across many mammals, actually have a powerful regulatory influence." Human chromosome 5 final sequence analysis released to public Disease genes, important regulatory elements populate vast terrain EurekAlert, Sepember 15 2004. http://www.eurekalert.org/pub_releases/2004-09/dgi-hc5091404.php Extract on Junk DNA: The spaces between the genes are as important as the genes themselves, said Eddy Rubin, JGI's director. "In addition to disease genes, other important genetic motifs gleaned from vast stretches of noncoding sequence have been found on Chromosome 5. Comparative studies conducted by our scientists of the vast gene deserts where it was thought there was little of value have shown that these regions, conserved across many mammals, actually have powerful regulatory influence." These gene-free stretches were previously considered "junk DNA," but in recent years those seemingly barren regions have taken on greater prominence as researchers have learned that they can control the activity of distant genes. Some of the noncoding regions have also stayed remarkably consistent compared with those in mice or fish rather than accumulating mutations over the course of evolution. "If you have such large human regions that stay conserved over vast evolutionary distances, it strongly supports the idea that they must contain something important," said Jeremy Schmutz, the informatics group leader at SHGC. Any mutation that appeared in those conserved regions was likely to have either killed the animal or made it less able to reproduce, preventing the mutation from making it to the next generation. So far, nobody has shown what role the conserved regions play. "What this says is that we don't know as much about this conserved stuff as we think we do," Schmutz said. The DNA sequence and comparative analysis of human chromosome 5 JEREMY SCHMUTZ, JOEL MARTIN, ASTRID TERRY, OLIVIER COURONNE, JANE GRIMWOOD, STEVE LOWRY, LAURIE A. GORDON, DUNCAN SCOTT, GARY XIE, WAYNE HUANG, UFFE HELLSTEN, MARY TRAN-GYAMFI, XINWEI SHE, SHYAM PRABHAKAR, ANDREA AERTS, MICHAEL ALTHERR, EVA BAJOREK, STACEY BLACK, ELBERT BRANSCOMB, CHENIER CAOILE, JEAN F. CHALLACOMBE, YEE MAN CHAN, MIRIAN DENYS, JOHN C. DETTER, JULIO ESCOBAR, DAVE FLOWERS, DEA FOTOPULOS, TIJANA GLAVINA, MARIA GOMEZ, EIDELYN GONZALES, DAVID GOODSTEIN, IGOR GRIGORIEV, MATTHEW GROZA, NANCY HAMMON, TREVOR HAWKINS, LAUREN HAYDU, SANJAY ISRANI, JAMIE JETT, KRISTEN KADNER, HEATHER KIMBALL, ARTHUR KOBAYASHI,, FREDERICK LOPEZ, YUNIAN LOU, DIEGO MARTINEZ, CATHERINE MEDINA, JENNA MORGAN, RICHARD NANDKESHWAR, JAMES P. NOONAN7, SAM PITLUCK, MARTIN POLLARD, PAUL PREDKI, JAMES PRIEST, LUCIA RAMIREZ, JAMES RETTERER, ALEX RODRIGUEZ, STEPHANIE ROGERS, ASAF SALAMOV, ANGELICA SALAZAR, NINA THAYER,, HOPE TICE, MING TSAI, ANNA USTASZEWSKA, NU VO, JEREMY WHEELER, KEVIN WU, JOAN YANG, MARK DICKSON, JAN-FANG CHENG, EVAN E. EICHLER6, ANNE OLSEN,, LEN A. PENNACCHIO,, DANIEL S. ROKHSAR, PAUL RICHARDSON, SUSAN M. LUCAS, RICHARD M. MYERS & EDWARD M. RUBIN. Nature 431, 268 - 274 (16 September 2004) Chromosome 5 is one of the largest human chromosomes and contains numerous intrachromosomal duplications, yet it has one of the lowest gene densities. This is partially explained by numerous gene-poor regions that display a remarkable degree of noncoding conservation with non-mammalian vertebrates, suggesting that they are functionally constrained. In total, we compiled 177.7 million base pairs of highly accurate finished sequence containing 923 manually curated protein-coding genes including the protocadherin and interleukin gene families. We also completely sequenced versions of the large chromosome-5-specific internal duplications. These duplications are very recent evolutionary events and probably have a mechanistic role in human physiological variation, as deletions in these regions are the cause of debilitating disorders including spinal muscular atrophy.