Research Question: Multiple morphological abnormalities of the flagella (MMAF) is characterized by excessive immotile spermatozoa with severe flagellar abnormalities in the ejaculate. Previous studies have reported a heterogeneous genetic profile associated with MMAF. What other genetic variants might explain the cause of MMAF?
Design: Whole-exome sequencing was conducted in a cohort of 90 Chinese patients with MMAF. The pathogenicity of identified mutations was assessed through electron microscopy and immunofluorescent examinations.
Results: Three unrelated men with bi-allelic DNAH2 variants were identified. Sanger sequencing verified that the six novel variants originated from every parent. All these variants were located at the conserved domains of DNAH2 and predicted to be deleterious by bioinformatic tools. Haematoxylin and eosin staining and scanning electron microscopy revealed that spermatozoa harbouring DNAH2 variants displayed severely aberrant morphology mainly with absent and short flagella (≥78%). Moreover, transmission electron microscopy revealed the obvious absence of a central pair of microtubules and inner dynein arms in the spermatozoa with mutated DNAH2. Immunofluorescence data further validated these findings, showing reduced DNAH2 protein expression in the spermatozoa with DNAH2 variants, compared with normal spermatozoa. Intracytoplasmic sperm injection using spermatozoa from the three men with mutated DNAH2 resulted in blastocyst formation in all cases. Embryo transfer was carried out in two couples, both resulting in clinical pregnancy.
Conclusions: These experimental and clinical data suggest that bi-allelic DNAH2 variants might induce MMAF-associated asthenoteratozoospermia, which can be overcome through intracytoplasmic sperm injection. These findings contribute to the knowledge of the genetic landscape of asthenoteratozoospermia and clinical counselling of male infertility.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1016/j.rbmo.2021.01.011 | DOI Listing |
J Hum Genet
November 2024
Inserm U1169, now at MIRCEN, Commissariat à l'Énergie Atomique, Fontenay-aux-Roses, France.
Hum Reprod
May 2024
Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.
Prog Neuropsychopharmacol Biol Psychiatry
March 2024
Key Laboratory of Trace Elements and Endemic Diseases of National Health and Family Planning Commission, Key Laboratory of Environment and Genes Related to Diseases of Ministry of Education of China, Key Laboratory for Disease Prevention and Control and Health Promotion of Shaanxi Province, School of Public Health, Health Science Center, Xi'an Jiaotong University, Xi'an, P. R. China. Electronic address:
Background: Rare variants are believed to play a substantial role in the genetic architecture of mental disorders, particularly in coding regions. However, limited evidence supports the impact of rare variants on anxiety.
Methods: Using whole-exome sequencing data from 200,643 participants in the UK Biobank, we investigated the contribution of rare variants to anxiety.
Pharmgenomics Pers Med
April 2022
Department of Pulmonary and Critical Care Medicine, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, People's Republic of China.
Primary ciliary dyskinesia (PCD) is a rare genetic disease caused by mutations of genes coding motile-cilia-related proteins. variants can cause PCD via disrupting the assembling of inner dynein and dynein regulating complex in cilia and flagella, but none has been reported associated with multiple morphological abnormalities of the sperm flagella (MMAF). We identified and validated the disease-causing variants in our patient via whole-exome and Sanger sequencing.
View Article and Find Full Text PDFHum Reprod
December 2021
Department of Obstetrics/Gynecology, Joint Laboratory of Reproductive Medicine (SCU-CUHK), Key Laboratory of Obstetric, Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, West China Second University Hospital, Sichuan University, Chengdu, China.
Study Question: Can whole-exome sequencing (WES) and in vitro validation studies identify new causative genes associated with teratozoospermia, particularly for sperm head defect?
Summary Answer: We investigated a core group of infertile patients, including 82 cases with unexplained abnormal sperm head and 67 individuals with multiple morphological abnormalities of the sperm flagella (MMAF), and revealed rare and novel deleterious gene variants correlated with morphological abnormalities of the sperm head or tail defects.
What Is Known Already: Teratozoospermia is one of the most common factors causing male infertility. Owing to high phenotypic variability, currently known genetic causes of teratozoospermia can only explain a rather minor component for patients with anomalous sperm-head shapes, and the agents responsible for atypical sperm head shapes remain largely unknown.
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!