Project description:The Zika outbreak, spread by the Aedes aegypti mosquito, highlights the need to create high-quality assemblies of large genomes in a rapid and cost-effective fashion. Here, we combine Hi-C data with existing draft assemblies to generate chromosome-length scaffolds. We validate this method by assembling a human genome, de novo, from short reads alone (67X coverage, Sample GSM1551550). We then combine our method with draft sequences to create genome assemblies of the mosquito disease vectors Aedes aegypti and Culex quinquefasciatus, each consisting of three scaffolds corresponding to the three chromosomes in each species. These assemblies indicate that virtually all genomic rearrangements among these species occur within, rather than between, chromosome arms. The genome assembly procedure we describe is fast, inexpensive, accurate, and can be applied to many species.
Project description:We describe a multiple de novo CNV (MdnCNV) phenomenon in which individuals with genomic disorders carry five to ten constitutional de novo CNVs. Five such families are studied, which consists of four trios and one singleton. Various array platforms are used to interogate these families to identify de novo CNVs.
Project description:We describe a multiple de novo CNV (MdnCNV) phenomenon in which individuals with genomic disorders carry five to ten constitutional de novo CNVs. Five such families are studied, which consists of four trios and one singleton. Various array platforms are used to interogate these families to identify de novo CNVs.
Project description:We describe a multiple de novo CNV (MdnCNV) phenomenon in which individuals with genomic disorders carry five to ten constitutional de novo CNVs. Five such families are studied, which consists of four trios and one singleton. Various array platforms are used to interogate these families to identify de novo CNVs.
Project description:We describe a multiple de novo CNV (MdnCNV) phenomenon in which individuals with genomic disorders carry five to ten constitutional de novo CNVs. Five such families are studied, which consists of four trios and one singleton. Various array platforms are used to interogate these families to identify de novo CNVs.
Project description:We used an approach combining PacBio data and published Illumina reads to de novo assemble D. busckii contigs. We generated Hi-C data from D. busckii embryos to order these contigs into chromosome-length scaffolds. For D. virilis we generated Hi-C data to order and orient the published Dvir_caf1 scaffolds into chromosome-length assemblies. Furthermore, we compared Hi-C matrices from these two new assemblies with D. melanogaster with respect to synteny blocks and dosage compensation as a chromosome-wide gene-regulatory mechanism.
Project description:The ability of centromeres to alternate between active and inactive states indicates significant epigenetic elements controlling centromere assembly and centromere function. In maize (Zea mays), misdivision of the B chromosome centromere on a translocation with the short arm of chromosome 9 (TB-9Sb) can produce many variants with varying centromere sizes and centromeric DNA sequences. In derivatives of TB-9Sb, we found a de novo centromere on chromosome telo-3-3, which has no canonical centromeric repeat sequences. This centromere is derived from a 288-kb region on the short arm of chromosome 9, and is 19 megabases (Mb) removed from the translocation breakpoint of chromosome 9 in TB-9Sb. This centromere is much smaller than normal ones but can be maintained through meiosis. The functional B centromere in progenitor telo2-2 is deleted from telo3-3 but some B-repeat sequences remain. The de novo centromere of telo3-3 becomes inactive in three further derivatives with new centromeres being formed elsewhere on the chromosomes. One such de novo centromere contains only 200-kb CENH3 binding domain. This 200-kb centromere is located 3 Mb removed from the translocation breakpoint in a new location. The deleted B centromere in telo3-3 is activated in two derivatives. Our results suggest that de novo centromere formation is more common than previously thought and can persist on chromosomal fragments without a canonical centromere providing implications for karyotype evolution. ChIP-seq was carried out with anti-CENH3 antibodies using material from young leaves with control, telo3-3 and its derivate.