Related Experiment Video
Updated: Jun 30, 2026
Mapping Infant Immunity with Minimal Input: Integrative Single-Cell and Multiomic Profiling
Published on: April 3, 2026
Archived unfrozen neonatal blood spots are amenable to quantitative gene expression analysis
Peterson T Haak1, Julia V Busik, Eric J Kort
1Laboratory of Microarray Technology, Van Andel Research Institute, Grand Rapids, Mich. 49503, USA.
Background:
State laws in the USA mandate that blood be drawn from all newborn infants to screen for health-threatening conditions. These screening assays consume only a small portion of the blood samples, which are collected on filter paper ('Guthrie') cards. Many states archive unused blood spots, often in unrefrigerated storage.
Objectives:
While individual RNA transcripts have been identified from archived neonatal blood spots, no study to date has performed quantitative analysis of archived blood spot RNA.
Methods:
We demonstrate that RNA can be isolated and amplified from newborn blood spots stored unfrozen for as long as 9 years, and can be analyzed by microarray and qPCR.
Results:
Microarray assays of archived neonatal blood spots consistently detected 3,000-4,000 expressed genes with correlations of 0.90 between replicates. Blood spot mRNA is amenable to qPCR and we detected biologically relevant expression levels of housekeeping and immune-mediating genes.
Conclusions:
These experiments demonstrate the feasibility of using blood spots as a source of RNA which can be analyzed using quantitative microarray and qPCR assays. The application of these methods to the analysis of widely collected biological specimens may be a valuable resource for the study of perinatal determinants of disease development.
