Citation:
J Clin Endocrinol Metab. 2024 Nov 18;109(12):3282-3292. doi: 10.1210/clinem/dgae270. PMID: 38654471
Abstract:
Context
Congenital hypothyroidism (CH) is the most common endocrine disorder in neonates, but its etiology is still poorly understood.
Objective
We performed whole exome sequencing to identify a novel causative gene for CH and functional studies to validate its role in the occurrence of CH.
Methods
Whole exome sequencing in 98 CH patients not harboring known CH candidate genes and bioinformatic analysis were performed. Functional analysis was performed using morpholino, a synthetic short antisense oligonucleotide that contains 25 DNA bases on a methylene morpholine backbone, in zebrafish and CRISPR-Cas9-mediated gene knockout in mice.
Results
Eukaryotic translation initiation factor 4B (EIF4B) was identified as the most promising candidate gene. The EIF4B gene was inherited in an autosomal recessive model, and 1 patient with thyroid dysgenesis carried EIF4B biallelic variants (p.S430F/p.P328L). In zebrafish, the knockdown of eif4ba/b expression caused thyroid dysgenesis and growth retardation. Thyroid hormone levels were significantly decreased in morphants compared with controls. Thyroxine treatment in morphants partially rescued growth retardation. In mice, the homozygous conceptuses of Eif4b+/− parents did not survive. Eif4b knockout embryos showed severe growth retardation, including thyroid dysgenesis and embryonic lethality before E18.5.
Conclusion
These experimental data support a role for EIF4B function in the pathogenesis of the hypothyroid phenotype seen in CH patients. Our work indicates that EIF4B was identified as a novel candidate gene in CH. EIF4B is essential for animal survival, but further studies are needed to validate its role in the pathogenesis of CH.
Epub:
Not Epub
Link to Publication:
https://academic.oup.com/jcem/article-abstract/109/12/3282/7657055
Organism or Cell Type:
zebrafish
Delivery Method:
microinjection