Live 4D optical coherence tomography for early embryonic mouse cardiac phenotyping
OPTICAL METHODS IN DEVELOPMENTAL BIOLOGY IV
Authors: Lopez, Andrew L., III; Wang, Shang; Larin, Kirill V.; Overbeek, Paul A.; Larina, Irina V.
Abstract
Studying embryonic mouse development is important for our understanding of normal human embryogenesis and the underlying causes of congenital defects. Our research focuses on imaging early development in the mouse embryo to specifically understand cardiovascular development using optical coherence tomography (OCT). We have previously developed imaging approaches that combine static embryo culture, OCT imaging and advanced image processing to visualize the whole live mouse embryos and obtain 4D (3D+time) cardiodynamic datasets with cellular resolution. Here, we present the study of using 4D OCT for dynamic imaging of early embryonic heart in live mouse embryos to assess mutant cardiac phenotypes during development, including a cardiac looping defect. Our results indicate that the live 4D OCT imaging approach is an efficient phenotyping tool that can reveal structural and functional cardiac defects at very early stages. Further studies integrating live embryonic cardiodynamic phenotyping with molecular and genetic approaches in mouse mutants will help to elucidate the underlying signaling defects.
A new case of KIAA0753-related variant of Jeune asphyxiating thoracic dystrophy
EUROPEAN JOURNAL OF MEDICAL GENETICS
Authors: Faudi, Emilien; Brischoux-Boucher, Elise; Huber, Celine; Dabudyk, Thibaud; Lenoir, Marion; Baujat, Genevieve; Michot, Caroline; Van Maldergem, Lionel; Cormier-Daire, Valerie; Piard, Juliette
Abstract
A narrow thorax with shortening of long bones is usually pointing to dysfunction of the primary cilia corresponding clinically to ciliopathies with major skeletal involvement. Mutations in at least 23 genes are likely to correspond to this clinical presentation: IFT43/52/80/81/122/140/172, WDR19/34/35/60, DYNC2H1, DYNC2LI1, CEP120, NEK1, TTC21B, TCTEX1D2, INTU, TCTN3, EVC 1/2 and KIAA0586. In addition to these, KIAA0753 variants were recently described in seven patients with Jeune asphyxiating thoracic dystrophy (ATD) (two first cousins, one unrelated patient and one fetus), Joubert syndrome (two siblings) and orofaciodigital syndrome type 6 (one patient). We present the clinical characteristics of a eighth such patient. This 4 year-old boy with narrow thorax, short limbs, severe respiratory and feeding difficulties from birth on had a history of hypotonia and developmental delay. On skeletal survey, short tubular bones (height - 5,5 SD) and a trident appearance of the pelvis were seen. Brain MRI showed cervical canal stenosis. Renal function was normal and moderate hepatomegaly was noted. A homozygous c.943C > T mutation in KIAA0753 was identified on whole exome sequencing, resulting in Gln315Ter premature termination of the corresponding protein. This case provides confirmation of an additional molecular basis for skeletal dysplasia and illustrates how ciliopathies due to mutations in a single gene may present as apparently distinct syndromes.