Matthew-Wood syndrome (MWS) is a rare autosomal recessive disorder caused by pathogenic variants of the STRA6 gene. Several studies in the available literature comprise patients with pathogenic variants of gene STRA6 with various phenotypic expressions: from lethal forms of MWS to non-lethal anophthalmia. These reports mainly describe new pathogenic variants and phenotypic expression but do not describe medical or paramedical care for the affected families. In our case report, we describe the second case of MWS in the same family and the benefits of including the patient's family in the perinatal palliative care program. The first pregnancy was terminated with a cesarean section; the boy was intubated in the delivery room and died soon after. The mother was not allowed to say farewell or keep any remembrances of her child. In the second pregnancy, the family was involved in the perinatal palliative care program, and all paramedical aspects, crucial from the parent's perspective, were planned and implemented. Palliative perinatal care enables complex care for the pregnant woman and her family. The possibility of palliative perinatal care is significant in decision-making in families with a high risk of lethal disease in subsequent pregnancies.

Matthew-Wood syndrome represents a rare genetic disorder characterized by diaphragmatic defects, pulmonary hypoplasia, micro- or anophthalmia, and cardiac defects. Most cases are lethal with very few infants living beyond a few years of life. Siblings with this diagnosis have been reported but never twins. In this article, we provided a review and discussion of this syndrome following its presentation in monochorionic, diamnionic twin females.

Retinoic acid (RA) signalling is essential for heart development, and dysregulation of the RA signalling can cause several types of cardiac outflow tract (OFT) defects, the most frequent congenital heart disease (CHD) in humans. Matthew-Wood syndrome is caused by inactivating mutations of a transmembrane protein gene STRA6 that transports vitamin A (retinol) from extracellular into intracellular spaces. This syndrome shows a broad spectrum of malformations including CHD, although murine Stra6-null neonates did not exhibit overt heart defects. Thus, the detailed mechanisms by which STRA6 mutations could lead to cardiac malformations in humans remain unclear. Here, we investigated the role of STRA6 in the context of human cardiogenesis and CHD. To gain molecular signatures in species-specific cardiac development, we first compared single-cell RNA sequencing (RNA-seq) datasets, uniquely obtained from human and murine embryonic hearts. We found that while STRA6 mRNA was much less frequently expressed in murine embryonic heart cells derived from the Mesp1+ lineage tracing mice (Mesp1Cre/+; Rosa26tdTomato), it was expressed predominantly in the OFT region-specific heart progenitors in human developing hearts. Next, we revealed that STRA6-knockout human embryonic stem cells (hESCs) could differentiate into cardiomyocytes similarly to wild-type hESCs, but could not differentiate properly into mesodermal nor neural crest cell-derived smooth muscle cells (SMCs) in vitro. This is supported by the population RNA-seq data showing down-regulation of the SMC-related genes in the STRA6-knockout hESC-derived cells. Further, through machinery assays, we identified the previously unrecognized interaction between RA nuclear receptors RARα/RXRα and TBX1, an OFT-specific cardiogenic transcription factor, which would likely act downstream to STRA6-mediated RA signalling in human cardiogenesis. Our study highlights the critical role of human-specific STRA6 progenitors for proper induction of vascular SMCs that is essential for normal OFT formation. Thus, these results shed light on novel and human-specific CHD mechanisms, driven by STRA6 mutations.

Syndromic microphthalmia-9 (MCOPS9) is a rare autosomal recessive disorder caused by mutations in STRA6, an important regulator of vitamin A and retinoic acid metabolism. This disorder is characterized by bilateral clinical anophthalmia, pulmonary hypoplasia/aplasia, cardiac malformations, and diaphragmatic defects. The clinical characteristics of this disorder have not been fully determined because of the rarity of clinical reports. A comprehensive genotyping examination including copy number variation sequencing (CNV-Seq) and whole-exome sequencing (WES) was applied to a fetus of Han Chinese with bilateral anophthalmia, bilateral pulmonary agenesis, interrupted aortic arch type A, and left ventricular non-compaction (LVNC). No aneuploidy or pathogenic CNV were identified by CNV-seq. WES analysis revealed a previously reported homozygous splice site (NM_022369.4:c.113+3_113+4del) in the STRA6 gene. This variant was confirmed by Sanger sequencing. The diagnosis of MCOPS9 was confirmed given the identification of the STRA6 mutation and the association of bilateral anophthalmia, pulmonary agenesis, and cardiac malformations. This case adds to the phenotypic spectrum of MCOPS9, supporting the association with LVNC, and the presence of interruption of aortic arch further demonstrates the variability of the cardiac malformations.