Patient-specific genomics and cross-species functional analysis implicate LRP2 in hypoplastic left heart syndrome
- Mayo Clinic, United States
- Sanford Burnham Prebys Medical Discovery Institute, United States
- University of California San Diego, United States
Abstract
Congenital heart diseases (CHDs), including hypoplastic left heart syndrome (HLHS), are genetically complex and poorly understood. Here, a multi-disciplinary platform was established to functionally evaluate novel CHD gene candidates, based on whole genome and iPSC RNA sequencing of a HLHS family-trio. Filtering for rare variants and altered expression in proband iPSCs prioritized 10 candidates. siRNA/RNAi-mediated knockdown in generic human iPSC-derived cardiomyocytes (hiPSC-CM) and in developing Drosophila and zebrafish hearts revealed that LDL receptor-related protein LRP2 is required for cardiomyocyte proliferation and differentiation. Consistent with hypoplastic heart defects, compared to patents the proband's iPSC-CMs exhibited reduced proliferation. Interestingly, rare, predicted-damaging LRP2 variants were enriched in a HLHS cohort; however, understanding their contribution to HLHS requires further investigation. Collectively, we have established a multi-species high-throughput platform to rapidly evaluate candidate genes and their interactions during heart development, which are crucial first steps towards deciphering oligogenic underpinnings of CHDs, including maladaptive left hearts.
Data availability
Sequencing data are deposited in the NCBI Sequence Read Archive (SRA) database with accession numbers: SRS1417684 (proband iPSCs), SRS1417685 (paternal iPSCs), SRS1417686 (maternal iPSCs), SRS1417695 (proband d25 differentiated cells), SRS1417696 (paternal d25 differentiated cells), SRS1417714 (maternal d25 differentiated cells)
Article and author information
Author details
Funding
Todd and Karen Wanek Family Program for Hypoplastic Left Heart Syndrome, Mayo Clinic Foundation, Rochester, MN (SAN-233970)
- Alexandre R Colas
- Rolf Bodmer
National Institutes of Health (HL054732)
- Rolf Bodmer
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Antje Ebert
Ethics
Animal experimentation: SBP has retained the services of a veterinarian who is a diplomat of the American College of Laboratory Animal Medicine. Close contact with Animal Facility personnel is maintained through telephone calls and on-campus visits once a week. This person is a member of the Institute's Animal Care and Use Committee (IACUC)and attends monthly meetings. This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to the Institute's Animal Care and Use Program, which is accredited by AAALAC International, and a Multiple Project Assurance A3053-1 is on file in the OLAW, DHHS. The protocol was approved by SBP IACUC (Permit Number: 19-087). Animals are euthanized after filming hearts by an overdose of anesthetic (3-aminobenzoic acid ethyl ester (MS-222) at 250-300 mg/L.
Human subjects: Written informed consent was obtained for the index family and an HLHS cohort, under a research protocol approved by the Mayo Clinic Institutional Review Board (11-000114 "Genetic Investigations in Hypoplastic Left Heart Syndrome").
Version history
- Received: June 1, 2020
- Accepted: September 29, 2020
- Accepted Manuscript published: October 2, 2020 (version 1)
- Version of Record published: October 22, 2020 (version 2)
- Version of Record updated: November 23, 2020 (version 3)
Copyright
© 2020, Theis et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 2,251
- views
-
- 281
- downloads
-
- 20
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
Patient-specific genomics and cross-species functional analysis implicate LRP2 in hypoplastic left heart syndrome
eLife 9:e59554.
https://doi.org/10.7554/eLife.59554
Further reading
-
- Genetics and Genomics
- Immunology and Inflammation
Transposable elements (TEs) are repetitive sequences representing ~45% of the human and mouse genomes and are highly expressed by medullary thymic epithelial cells (mTECs). In this study, we investigated the role of TEs on T-cell development in the thymus. We performed multiomic analyses of TEs in human and mouse thymic cells to elucidate their role in T-cell development. We report that TE expression in the human thymus is high and shows extensive age- and cell lineage-related variations. TE expression correlates with multiple transcription factors in all cell types of the human thymus. Two cell types express particularly broad TE repertoires: mTECs and plasmacytoid dendritic cells (pDCs). In mTECs, transcriptomic data suggest that TEs interact with transcription factors essential for mTEC development and function (e.g., PAX1 and REL), and immunopeptidomic data showed that TEs generate MHC-I-associated peptides implicated in thymocyte education. Notably, AIRE, FEZF2, and CHD4 regulate small yet non-redundant sets of TEs in murine mTECs. Human thymic pDCs homogenously express large numbers of TEs that likely form dsRNA, which can activate innate immune receptors, potentially explaining why thymic pDCs constitutively secrete IFN ɑ/β. This study highlights the diversity of interactions between TEs and the adaptive immune system. TEs are genetic parasites, and the two thymic cell types most affected by TEs (mTEcs and pDCs) are essential to establishing central T-cell tolerance. Therefore, we propose that orchestrating TE expression in thymic cells is critical to prevent autoimmunity in vertebrates.
-
- Genetics and Genomics
The ‘diabetic bone paradox’ suggested that type 2 diabetes (T2D) patients would have higher areal bone mineral density (BMD) but higher fracture risk than individuals without T2D. In this study, we found that the genetically predicted T2D was associated with higher BMD and lower risk of fracture in both weighted genetic risk score (wGRS) and two-sample Mendelian randomization (MR) analyses. We also identified ten genomic loci shared between T2D and fracture, with the top signal at SNP rs4580892 in the intron of gene RSPO3. And the higher expression in adipose subcutaneous and higher protein level in plasma of RSPO3 were associated with increased risk of T2D, but decreased risk of fracture. In the prospective study, T2D was observed to be associated with higher risk of fracture, but BMI mediated 30.2% of the protective effect. However, when stratified by the T2D-related risk factors for fracture, we observed that the effect of T2D on the risk of fracture decreased when the number of T2D-related risk factors decreased, and the association became non-significant if the T2D patients carried none of the risk factors. In conclusion, the genetically determined T2D might not be associated with higher risk of fracture. And the shared genetic architecture between T2D and fracture suggested a top signal around RSPO3 gene. The observed effect size of T2D on fracture risk decreased if the T2D-related risk factors could be eliminated. Therefore, it is important to manage the complications of T2D to prevent the risk of fracture.
