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Title: Sequencing historical specimens: successful preparation of small specimens with low amounts of degraded DNA
Abstract

Despite advances that allowDNAsequencing of old museum specimens, sequencing small‐bodied, historical specimens can be challenging and unreliable as many contain only small amounts of fragmentedDNA. Dependable methods to sequence such specimens are especially critical if the specimens are unique. We attempt to sequence small‐bodied (3–6 mm) historical specimens (including nomenclatural types) of beetles that have been housed, dried, in museums for 58–159 years, and for which few or no suitable replacement specimens exist. To better understand ideal approaches of sample preparation and produce preparation guidelines, we compared different library preparation protocols using low amounts of inputDNA(1–10 ng). We also explored low‐cost optimizations designed to improve library preparation efficiency and sequencing success of historical specimens with minimalDNA, such as enzymatic repair ofDNA. We report successful sample preparation and sequencing for all historical specimens despite our low‐inputDNAapproach. We provide a list of guidelines related toDNArepair, bead handling, reducing adapter dimers and library amplification. We present these guidelines to facilitate more economical use of valuableDNAand enable more consistent results in projects that aim to sequence challenging, irreplaceable historical specimens.

 
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NSF-PAR ID:
10034474
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Molecular Ecology Resources
Volume:
17
Issue:
6
ISSN:
1755-098X
Page Range / eLocation ID:
p. 1183-1201
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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