A Novel c.968C > T homozygous Mutation in the Polynucleotide Kinase 3' - Phosphatase Gene Related to the Syndrome of Microcephaly, Seizures, and Developmental Delay.

Microcephaly is defined by a head circumference that is at least two standard deviations below the mean for age and sex of the general population in a specific race. Primary microcephaly may occur as an isolated inborn error, which may damage to the central nervous system or as part of the congenital abnormalities associated with genetic syndrome, affecting multiple organ systems. One of the syndromic forms consists of microcephaly, seizures, and developmental delay caused by biallelic mutations in the gene that encode polynucleotide kinase 3' - phosphatase protein (PNKP). In this article, we reported a newborn male who presented with microcephaly, severe developmental delay, and early-onset refractories seizures, caused by a novel homozygous mutation of the PNKP gene.

Homozygous truncating mutation in prenatally expressed skeletal isoform of TTN gene results in arthrogryposis multiplex congenita and myopathy without cardiac involvement.

We report the case of a newborn with arthrogryposis multiplex congenita and severe axial hypotonia without cardiac involvement in which, using a customized targeted next-generation sequencing assay for 64 myopathy-associated genes, we detected a novel homozygous truncating mutation, c.38661_38665del, in exon 197 of the TTN gene that is expressed only in the fetal skeletal isoform. Its pathogenicity is supported by evidence of maternal isodisomy for chromosome 2. Muscle pathology showed fibers with core-like areas devoid of oxidative staining and cytoplasmic bodies. Electron microscopy showed the replacement of the sarcomeric structure with filamentous material. Identification of this mutation expands the phenotypic spectrum of the TTN gene and shows for the first time that a mutation not found in adult TTN isoforms is involved in the development of a neuromuscular disorder. TTN mutations should be considered in all severe congenital myopathies with arthrogryposis without cardiac involvement.

[X-chromosome-linked ichthyosis associated to epilepsy, hyperactivity, autism and mental retardation, due to the Xp22.31 microdeletion]. / Ictiosis ligada al cromosoma X asociada a epilepsia, hiperactividad, autismo y retraso mental, por microdeleción Xp22.31.

X-chromosome-linked ichthyosis is caused by mutation or deletion of the STS gene associated with a deficiency of the enzyme steroid sulphatase, located in the distal part of the short arm of the X chromosome (Xp22.3-pter), close to the pseudo-autosomal region. Depending on its size, it can present as an isolated entity or combined with a syndrome caused by neighbouring genes, thus associating itself with other monogenic diseases as well as other mental disorders. The most relevant findings from the literature review are the importance of the Xp22.3-pter region and the higher incidence of neurological disorders among males (attention deficit hyperactivity disorder, autism and X-linked mental retardation). The role and implication of these genes in the disease are discussed and the authors suggest a possible contribution of the gene PNPLA4, which was originally described as GS2 and codes for calcium-independent phospholipase A2 beta, involved in lipoprotein metabolism, as one of the causes of autism. Improvements have been observed following treatment with citicoline, thanks to the role this nootropic plays in the biosynthesis of structural phospholipids involved in the formation and repair of the neuronal membrane.