A 360-kb interchromosomal duplication of the human HYDIN locus

DOE Joint Genome Institute and Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
Genomics (Impact Factor: 2.79). 01/2007; 88(6):762-71. DOI: 10.1016/j.ygeno.2006.07.012

ABSTRACT The HYDIN gene located in human chromosome band 16q22.2 is a large gene encompassing 423 kb of genomic DNA that has been suggested as a candidate for an autosomal recessive form of congenital hydrocephalus. We have found that the human HYDIN locus has been very recently duplicated, with a nearly identical 360-kb paralogous segment inserted on chromosome 1q21.1. The duplication, among the largest interchromosomal segmental duplications described in humans, is not accounted for in the current human genome assembly and appears to be part of a greater than 550-kb contig that must lie within 1 of the 11 sequence gaps currently remaining in 1q21.1. Both copies of the HYDIN gene are expressed in alternatively spliced transcripts. Elucidation of the role of HYDIN in human disease susceptibility will require careful discrimination among the paralogous copies.

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    • "proteins found in the anchoring filaments of skin keratinocytes that strengthen attachment to the dermis (Gerecke et al., 1994). The predicted intracellular portion of H04D03.1 also has similarity to human hydin (E value 1.7), a hydrocephalus-inducing protein of 5120 amino acids (Davy and Robinson, 2003; Doggett et al., 2006) (Fig. S4). "
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    Developmental Biology 02/2011; 352(2):243-53. DOI:10.1016/j.ydbio.2011.01.024 · 3.64 Impact Factor
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    • "We divided the genome into nonoverlapping regions of 100 kb. We excluded 37 regions containing sites where all individuals in both populations were heterozygous (Supplemental Table 1), as these may represent variation between undocumented paralogs (Doggett et al. 2006). Thus, our final data set consisted of 10,497 regions of 100 kb, each with over 500 bp of exon sequence, comprising 25,769 kb of exome sequence in each of 10 individuals. "
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    Genome Research 10/2010; 20(10):1327-34. DOI:10.1101/gr.106161.110 · 13.85 Impact Factor
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    • "Three of these four heterozygous SNPs (rs12149070, rs783756 and rs7206076) were found to be placed within HYDIN locus, a large gene of 423 kb containing 20 SNPs, of which a 360 kb paralogous segment is inserted on chromosome 1q21.1. The high level of sequence identity between the two loci (Doggett et al., 2006), led us to consider these heterozygous alleles as probably being " misgenotyped " . Subsequently, additional genotyping was carried out using Human610-Quad BeadChips on an unaffected sibling (IV:7), who was found to share 1,050 consecutive SNPs (identical by state) across the 46.44 Mb homozygous track, dividing the linkage area into two different loci of 26. "
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