How do I go about using the Source BioScience LifeSciences
These are the minimum things you need to do:
- get your sequencing template prepared by PCR or plasmid
- work out what primers you want to use for your sequencing; are
they in our list of standard primers we supply for free?
- fill out an on-line sequence order form including the
declarations on Genetically Modified Organisms (GMO) and VAT.
- send all of the above to the address on the bottom of the order
What concentrations of DNA and primers do I need to send?
We find that sequencing reactions are quite robust but we do
need to know roughly what these values are. We aim for the
concentrations of DNA to be 1ng/μl per 100bp for PCR products,
100ng/μl for plasmids and 3.2pmol/μl for oligos. Volumes supplied
should be 6μl per sequencing reaction requested of plasmid or PCR
product and 10μl of your oligos per reaction requested.
Do PCR products need to be cleaned before being sent for
PCR templates for sequencing must have been cleaned up to remove
unincorporated reactants before sending to us. In our hands all the
commercial kits work OK. We will not accept liability for failed
sequences when in our opinion the templates are poorly
Will you make DNA template?
Yes. We have a standard protocol for extracting plasmids and for
making PCRs. If you send us cultures for plasmid extraction then
you must complete the declaration on GMO on the sequencing order
form. If you fail to complete this then any material you send us
will probably be destroyed. PCR primers must accompany PCR reaction
requests. We make only one attempt at these using our standard
conditions or conditions that you supply. If you decide that we
need to work further on the PCR (titration) then further costs will
be incurred. It is always best to contact us in advance of making
template preparation requests.
Do you make oligos?
No. We are not an oligo supplier although we do have stocks of
standard primers that we use at no charge to customers on their
experiments. We do have a preferred oligo supplier and can get
oligos synthesized quickly and cheaply for customers.
What are your standard sequencing primers?
M13F, M13R, T7F, T7R, T3, SP6, SK, KS and growing every day! The
sequences are available on our web site.
Tell me about your registration to handle genetically modified
We are registered with the Health and Safety Executive (HSE) for
the safe handling of your GMO. This registration is only valid if
the GMO declaration is completed by you when sending cultures. We
are unable to accept GMO when this declaration is not completed and
your materials will probably be destroyed.
How much does all this cost?
Not very much! Sequencing prices are falling all the time and we
pass on these savings immediately to our customers. However, like
all businesses we recognize the benefits of economies of scale.
This means that the more sequencing you send (or commit to in any
year) the lower your price will be.
So you're doing it on the cheap?
On the contrary. Our sequencing operation uses over £½ million
worth of hardware, including the latest ABI 3730 DNA sequencing
What experience have you got then?
Source BioScience LifeSciences has been around, in the form of
HGMP, MRC Source BioScience LifeSciences and the Linkage Hotel
at the HGMP-RC for almost 10 years. The sequencing team has more
than 10 years experience of making reads. In the past 5 years
members of our team have contributed over 2 million reads to the UK
Mouse Sequencing Consortium and then the Fugu sequence
So you only deal with large projects?
No. The minimum number of reads that we accept is 1.
What read lengths do you get?
Unlike some sequencing operations we don't make any promises on
sequencing read length - we know that in isolation these promises
are always wrong. On average we get about 750bp to 850bp of
quality clipped sequence, although our reads are much
longer at over 1kb.
But your competitors promise longer reads than that!
We can't make these promises and are surprised when others do.
There are lots of reasons why sequencing reactions fail and most of
them are nothing to do with us or you - that's biology. Repetitive
elements and secondary structure account for short reads as will
poorly purified templates. Of course a PCR product of 600bp will
never give you a 650bp sequencing reaction. All of these things
bring our averages down from the actual standard read length of a
sequencing pass that is much higher.
What can you do about these biological sequencing fails?
We have a number of strategies to improve templates (Template
Rescue Service, TRS) and to cover repetitive sequence or sequence
with secondary structure (Secondary Structure Solution, SSS). We
purchase some commercial reagents and have a few secret tricks for
crossing these regions. Please contact us if you have a special
Do I pay for sequencing reaction fails?
Yes. We have controls in place such that we are confident that
sequencing fails are generally the responsibility of the customer
because of poorly prepared or purified templates, or bad oligos.
You will always be sent failed read chromatograms for you to
inspect them. However, when reads are sent to you, you can always
ask for failed reads to be repeated and we are very happy to do so.
Experience shows ~95% of failed reads fail again. In this case we
will charge double for the fail if we repeat it. Obviously, if the
failed read passes (5% of occasions) on repeat, we concede this to
be our responsibility and you only pay once.
What is your turn-around time?
Between 1 and 2 days but this depends on the level of contract
research requested and the number of reads. If you want to send us
more than 90 reads at once we suggest you contact us in advance.
Machine breakdown has caused turnaround time to be longer than this
but we always keep a capillary sequencer in reserve.
How is data returned to me?
Most customers want their reads to be delivered by email
attachment. For larger orders we can set up secure FTP sites or
make CD-ROMs. Please contact us if you have any special
How do I know you won't make an error with my important
We have laboratory information management systems (LIMS) in
place. Your material is assigned a 96 well plate names and position
when we receive it. From then on it is handled in this format and
tracked with bar coding at every stage. We do not promise that
mistakes cannot be made - we do promise that we have minimised
these chances and that we will strive to always get you the best
possible data. We will always be honest with you about your
sequencing and your plates controls are always stored and are
available for you to see. In the event of any dispute between
customers and ourselves we will generally offer to make repeat
samples for free.
I still have some questions...
contact us now.