MinION™: New, Long Read, Portable Nucleic Acid Sequencing Device

Detection of an unusual G8P[8] rotavirus in a Rotarix-vaccinated child with acute gastroenteritis using Nanopore MinION sequencing: A case report

RATIONALE

Rotavirus is routinely diagnosed by the detection of antigens or the viral genome. However, these tests have limitations, in that they do not detect all rotavirus strains.

PATIENT CONCERNS

We present a case of a 27-month-old girl who was hospitalized for 4 days with severe gastroenteritis, including high fever, vomiting, diarrhea, mild dehydration, and periumbilical pain. Notably, the patient previously received the Rotarix vaccine.

DIAGNOSES

The laboratory tests were negative for rotavirus, astrovirus, adenovirus, and norovirus as well as common diarrhea-causing bacteria. Human-bovine recombinant rotavirus was detected by MinION sequencing.

INTERVENTIONS

To investigate the cause agents from the unexplained severe gastroenteritis infant, the stool sample was prepared by random amplification for Nanopore MinION sequencing.

OUTCOMES

Treatment through the administration of ORS solution and galtase powder with probiotics was successful after the diagnosis of unusual rotavirus infection.

LESSONS

This case report is the first detection of an unusual human-bovine recombinant rotavirus in an idiopathic gastroenteritis using Nanopore MinION sequencing.

A new hybrid approach for MHC genotyping: high-throughput NGS and long read MinION nanopore sequencing, with application to the non-model vertebrate Alpine chamois (Rupicapra rupicapra)

The major histocompatibility complex (MHC) acts as an interface between the immune system and infectious diseases. Accurate characterization and genotyping of the extremely variable MHC loci are challenging especially without a reference sequence. We designed a combination of long-range PCR, Illumina short-reads, and Oxford Nanopore MinION long-reads approaches to capture the genetic variation of the MHC II DRB locus in an Italian population of the Alpine chamois (Rupicapra rupicapra). We utilized long-range PCR to generate a 9 Kb fragment of the DRB locus. Amplicons from six different individuals were fragmented, tagged, and simultaneously sequenced with Illumina MiSeq. One of these amplicons was sequenced with the MinION device, which produced long reads covering the entire amplified fragment. A pipeline that combines short and long reads resolved several short tandem repeats and homopolymers and produced a de novo reference, which was then used to map and genotype the short reads from all individuals. The assembled DRB locus showed a high level of polymorphism and the presence of a recombination breakpoint. Our results suggest that an amplicon-based NGS approach coupled with single-molecule MinION nanopore sequencing can efficiently achieve both the assembly and the genotyping of complex genomic regions in multiple individuals in the absence of a reference sequence.

The Oxford Nanopore MinION: delivery of nanopore sequencing to the genomics community

Nanopore DNA strand sequencing has emerged as a competitive, portable technology. Reads exceeding 150 kilobases have been achieved, as have in-field detection and analysis of clinical pathogens. We summarize key technical features of the Oxford Nanopore MinION, the dominant platform currently available. We then discuss pioneering applications executed by the genomics community.

Characterization of Two Multidrug-Resistant IncA/C Plasmids from the 1960s by Using the MinION Sequencer Device

Two A/C incompatibility group (IncA/C family) plasmids from the 1960s have been sequenced and classified into the A/C₂ type 1 group. R16a and IP40a contain novel antibiotic resistance islands and a complete GIsul2 genomic island not previously found in the family. In the 173.1-kb R16a, the 29.9-kb antibiotic resistance island (ARI) is located in a unique backbone position not utilized by ARIs. ARI_R16a consists of Tn1, Tn6020, and Tn6333, harboring the resistance genes bla_TEM-1D and aphA1b and a mer module, respectively; a truncated Tn5393 copy; and a gene cluster with unknown function. Plasmid IP40a is 170.4 kb in size and contains a 5.6-kb ARI inserted into the kfrA gene. ARI_IP40a carrying bla_TEM-1D and aphA1b genes is composed of Tn1 with a Tn6023 insertion. Additionally, IP40a harbors single IS2, IS186, and Tn1000 insertions scattered in the backbone; an IS150 copy in GIsul2; and a complete Tn6333 carrying a mer module at the position of ARI_R16a Loss of resistance markers in R16a, IP40a, and R55 was observed during stability tests. Every phenotypic change proved to be the result of recombination events involving mobile elements. Intramolecular transposition of IS copies that generated IP40a derivatives lacking large parts of the backbone could account for the formation of other family members, too. The MinION platform proved to be a valuable tool in bacterial genome sequencing since it generates long reads that span repetitive elements and facilitates full-length plasmid or chromosome assembly. Nanopore technology enables rapid characterization of large, low-copy-number plasmids and their rearrangement products.