How do I submit my index information into Lablink?

When accepting sequencing submissions in the Genomics Core, there may be instances where we have to contact you if there is an error with your submission form. The most common problems relate to index information. We have put together some instructions here that we hope should make things easier and help us to get started on your sequencing as soon as we can.

Please only follow these instructions if:

·        The index sequences you have used are visible in the index sequences tab of the submission form

·        There are fewer than 384 samples within your pool.

If the points above are not true, please see section, unspecified index further on in this blog.

1.      Completing the sample/reagent label field

1a. Navigate to the index sequences tab of the sample submission form.

1b. Search for your index sequences

1c. Copy the index name from column C of the index sequences tab, e.g A001-A005 to the column Sample/Reagent Label, of the submission form tab.

Figure 1-index sequences tab of the sample submission form

Figure2-submission form

      2. Completing the UDF/Index type field

2a. Select the correct UDF/Index type from the drop down menu on the submission form tab.

IMPORTANT –please make sure the Index type field matches column B of the index sequences tab. This ensures that your library goes through our acceptance step. Please see the two following examples. 

Example1- I am submitting a Truseq LT library consisting of 5 samples and used indexes A001-A005.

The sample/reagent label on the submission form should read A001-A005.
The UDF/index type should read Truseq LT.

 Figure 3 - The index type field next to these indexes is Truseq LT so this is what should be entered into the UDF/Index type field.

Figure 4- Submission form

In most cases, the Index type will match to the indexes you have used as expected. However there are now multiple kits available which share the same indexes.
Because of this, there may be some cases where the index sequences you select will have a different Index type to the library you have made. (see example 2 below) This may affect you if you are submitting for Nextera XT or Nextera.

Example 2- I used indexes N701-N501, N702-N501, N703-N501, N704-N501. I prepared the libraries using a Nextera XT library prep kit.

The sample/reagent label on the submission form should read N701-N501, N702-N501, N703-N501, N704-N501. The UDF/index type should read Nextera and not Nextera XT. This is because the UDF/Index type needs to match column B on the index sequences tab.

Figure 5 - The index type field next to these indexes is Nextera so this is what should be entered into the UDF/Index type field

 

3. Unspecified Index

If your pool has index sequences not present in the index sequences tab OR if you have a pool which is made up of more than 384 samples, you will need to submit as unspecified index.

In the submission form:

·        Sample/reagent label should read – unspecified

·        UDF/Index type should read –Unspecified (other)

You should submit your pool as one row on the form. Libraries submitted as unspecified index cannot be demultiplexed by the Genomics Core but we do have a demultiplexing guide on lablink which should give some useful information.

Important-since we have no index sequence information, please write in the comments section of the form the index lengths for Index 1 and Index 2. Without this information your sequencing may be delayed whilst we contact you to check these parameters.
Once you have submitted your libraries, the Genomics Core would like to start working on your sequencing as soon as we can.

If the incorrect index type has been selected, we will need to delete your submission and we would ask you to submit again after making changes to your sample sheet and following the instructions above. Of course whilst this guide should be used to help you, we are always here to discuss this with you in person if you have any questions. Alternatively you can contact us on our helpdesk: genomics-helpdesk@cruk.cam.ac.uk 

Recent papers that the Genomics Core has helped with

I like to highlight some of the really interesting work we've been involved with, or that has come out of the Institute from time to time, and I recently updated our lab home page with links to a couple of papers.  i thought I'd take the opportunity to write about them in a bit more detail here. Many of you will already know I run the Genomics Core facility at CRUKs Cambridge Institute. We do a lot of Illumina sequencing! The lab works on a huge number of projects for the research groups here in the Institute, and also across many groups in Cambridge via a long-running sequencing collaboration. We do do some R&D work in my lab, but >90% of our efforts are working with, or for, other research groups.

The papers:

1. Pereira et al Nature Communications 2016: The somatic mutation profiles of 2,433 breast cancers refine their genomic and transcriptomic landscapes
2. Bruna et al Cell 2016: A Biobank of Breast Cancer Explants with Preserved Intra-tumor Heterogeneity to Screen Anticancer Compounds 
3. Lensing et al Nature Methods 2016: DSBCapture: in situ capture and sequencing of DNA breaks).
4. Murtaza et al Nature Communications 2015: Multifocal clonal evolution characterized using circulating tumour DNA in a case of metastatic breast cancer 

Highlights from the last years genomics research include work from the Caldas group who have completed three project over the lat year I've included here; 1) profiling of almost 2500 Breast Cancer patients for mutational analysis of 173 genes using a targeted pull-down (Pereira et al Nature Communications 2016); 2) cancer exomes from Murtaza et al,; 3) PDXs from Bruna et al.; and the Balasubramanian group who have shown that it is possible to capture and sequence double-strand DNA breaks (DSBs) in situ and directly map these at single-nucleotide resolution, enabling the study of DSB origin (Lensing et al. Nature Methods 2016). The rapid speed and unbiased nature of the genome-wide experiments being performed in the Institute, and often prepped and sequenced in the Genomics core continue to increase our understanding cancer biology.