Intronic OTOF mutation causes an atypical splicing defect resulting in auditory neuropathy spectrum disorder.

Pathogenic variants in OTOF cause auditory neuropathy spectrum disorder (ANSD), namely prelingual nonsyndromic ANSD and temperature-sensitive ANSD (TS-ANSD). All study subjects provided blood sample for genetic analysis and sequencing. Wholeexome sequencing was carried out to identify the causative pathogenic variant. RNAwas extracted to analyse the messenger RNA (mRNA) resulting from the transcription of OTOF. Here, we identified a family with OTOF-related ANSD. This disorder was caused by an intronic mutation in OTOF (NM_194248: c.2406>4A[G). In further analysis, we proved that this variant causes a splicing defect resulting in the omission of exon 20 from the mRNA transcribed from OTOF. In this study, we demonstrated that the variant is four nucleotides away from the conventional splicing site, and our findings suggest that splicing mechanisms need to be better understood, as well as how neighbouring regions may impact splicing.

A combination of two novels homozygous FCSK variants cause disorder of glycosylation with defective fucosylation: New patient and literature review.

Pathogenic variants in FCSK cause Congenital Disorder of Glycosylation with Defective Fucosylation-2 (FCSK-CDG; MIM: 618,324). It is a rare autosomal recessive genetic disease caused by defects in the L-fucose kinase, which is necessary for the fucose salvage pathway. Herein, we report two novel variants in an Iranian patient, the fourth individual with FCSK-CDG described in the literature. Two homozygous variants in FCSK (rs376941268; NM_145059.3: c.379C > A, p. Leu127Met and rs543223292; NM_145059.3: c.394G > C, p. Asp132His) were identified in the proband. Sanger sequencing conducted on his unaffected parents revealed that they were heterozygous for the same variants. The proband, a four-and-a-half year old Iranian male born to consanguineous parents, manifested Intellectual disability, growth delay, ophthalmic abnormalities, seizures, speech disorder, and feeding difficulties.

MCM2 mutation causes autosomal dominant nonsyndromic hearing loss (DFNA70): novel variant in the second family.

Pathogenic variants in MCM2 could result in mild to severe sensorineural hearing loss in the affected individuals (deafness, autosomal dominant 70; DFNA70; OMIM: 616968), an extremely rare autosomal dominant progressive disorder. Here, we report a novel missense variant (NM_004526:c.388C>T, p.R130C; Clinvar: SCV002072508) in MCM2 in an Iranian family identified by whole-exome sequencing and confirmed by Sanger sequencing. The heterozygous variant (NM_004526:c.388C>T, p.R130C) in MCM2 was identified in the proband and his mother. The proband is a nine-year-old male born to nonconsanguineous parents. The proband was characterized by nonsyndromic hearing loss, while his mother showed a mild form of the disorder. This study reports the second disease-causing variant in MCM2 in the world and confirms that hearing loss arising from variants in MCM2 is nonsyndromic. Nevertheless, as was reported in the previous family, phenotype could vary among the patients with the same variant.

Phenotypic spectrum of autosomal recessive Keratitis-Ichthyosis-Deafness Syndrome (KIDAR) due to mutations in AP1B1.

Inborn errors in copper metabolism result in a diverse set of abnormalities such as Wilson disease and MEDNIK syndrome. Homozygous pathogenic variants in AP1B1 lead to KIDAR (Keratitis-Ichthyosis-Deafness Syndrome). The main phenotypic features of KIDAR are ichthyosis, keratitis, erythroderma, and progressive hearing loss accompanied by developmental delay and failure to thrive. Herein, we describe a six-and-a-half-year-old boy with KIDAR caused by a novel pathogenic variant in AP1B1 (NM_001127.4:c.1263C > A, p.Tyr421*). The proband presented with ichthyosis, erythroderma, palmoplantar keratoderma, hearing loss, and corneal scarring. He also had hypotonia, global developmental delay, and photophobia. Lastly, we review all of the previously reported cases and the clinical features associated with KIDAR.

The effect of N-acetyl cysteine consumption on men with abnormal sperm parameters due to positive history of COVID-19 in the last three months.

Male infertility is an important factor accounting for 40-50% of infertility cases that may be due to disturbance in one of the parameters as concentration, motility and morphology observed in one or two semen analysis with an interval of 1 and 4 weeks. COVID-19 may affect male fertility through virus division, cytotoxic effects on testicular tissue and immunopathological effect. N-acetyl cysteine (NAC) improved sperm concentration and acrosome reaction while reducing reactive oxygen species (ROS) and oxidation of sperm DNA. This interventional study was conducted on 200 men who were referred to private infertility clinics for female factor (their previous semen analysis was normal) and got COVID-19 infection in the last 3 months showing an impairment of the latest semen analysis due to COVID. Men were placed in two groups of control (n = 100) and intervention (NAC consumption). Subjects who got COVID-19 infection had a significant impairment of sperm quality (sperm concentration, sperm motility, and normal sperm morphology) compared to their semen analysis evaluated before the COVID-19 infection. NAC consumption significantly improved sperm total motility, sperm morphology and sperm concentration. COVID-19 infection has a negative effect on sperm parameters. NAC supplementation may have positive effect on sperm parameters.

Phenotype of ST3GAL3 deficient patients: A case and review of the literature.

ST3GAL3 deficiency is an extremely rare autosomal recessive disorder caused by pathogenic mutations in the ST3GAL3 gene. Epilepsy, motor development delay, severe intellectual disability, and behavioral disorders have been reported to be associated with ST3GAL3 deficiency. In the present study, ST3GAL3 deficiency was caused by a homozygous splice-site mutation (NM_174964.4: c.936+1delG) in ST3GAL3. The patient described in this study was clinically similar to previously reported cases; nevertheless, we were able to detect repetitive behavior, previously not reported manifestations.