Identification of a male with fragile X syndrome through newborn screening

A pilot newborn screening (NBS) study for fragile X syndrome was recently conducted at the University of California, Davis Medical Center. The screening study identified a case of a male with the full mutation completely methylated and no detectable expression of the fragile X mental retardation-1 (FMR1) gene. The patient was initially seen in clinic at the MIND Institute, for medical follow-up and a genetic counseling session at the chronological age of 3 months. Since then, he has been seen in clinic every six months for follow up, medical examination and developmental assessments. Longitudinally administered developmental testing of the infant has revealed persistent delays in development, consistent with fragile X syndrome. Cascade testing revealed that the patient's mother and two siblings also have the full mutation. The patient has been receiving speech and language therapy, combined with physical and occupational therapies on a weekly basis since the age of one year. He is currently being treated with 2.5 mg of sertraline, which has been demonstrated to be helpful for improving language in young children with the syndrome

Group I metabotropic glutamate receptor mediated dynamic immune dysfunction in children with fragile X syndrome

BackgroundFragile X syndrome (FXS) is the leading cause of inheritable intellectual disability in male children, and is predominantly caused by a single gene mutation resulting in expanded trinucleotide CGG-repeats within the 5' untranslated region of the fragile X mental retardation (FMR1) gene. Reports have suggested the presence of immune dysregulation in FXS with evidence of altered plasma cytokine levels; however, no studies have directly assessed functional cellular immune responses in children with FXS. In order to ascertain if immune dysregulation is present in children with FXS, dynamic cellular responses to immune stimulation were examined.MethodsPeripheral blood mononuclear cells (PBMC) were from male children with FXS (n=27) and from male aged-matched typically developing (TD) controls (n=8). PBMC were cultured for 48 hours in media alone or with lipopolysaccharides (LPS; 1 μg/mL) to stimulate the innate immune response or with phytohemagglutinin (PHA; 8 μg/mL) to stimulate the adaptive T-cell response. Additionally, the group I mGluR agonist, DHPG, was added to cultures to ascertain the role of mGluR signaling in the immune response in subject with FXS. Supernatants were harvested and cytokine levels were assessed using Luminex multiplexing technology.ResultsChildren with FXS displayed similar innate immune response following challenge with LPS alone when compared with TD controls; however, when LPS was added in the presence of a group I mGluR agonist, DHPG, increased immune response were observed in children with FXS for a number of pro-inflammatory cytokines including IL-6 (P=0.02), and IL-12p40 (P<0.01). Following PHA stimulation, with or without DHPG, no significant differences between subjects with FXS and TD were seen.ConclusionsIn unstimulated cultures, subjects with FXS did not display altered dynamic immune response to LPS or PHA alone; however, subjects with FXS showed an altered response to co-current stimulation of LPS and DHPG, such that subjects with FXS failed to inhibit production of pro-inflammatory cytokines, suggesting a role of group I mGluR signaling in innate immune responses in FXS

Robust Screening and Cascade Testing for Fragile X Expansions in a Large Multigenerational Family Identify Many Affected Individuals: An Experience in the Remote Area of Indonesia

Fragile X Syndrome (FXS) is the most common known inherited form of intellectual disability (ID), caused by a CGG repeat expansion of the FMR1 gene. The aimed of the study was to screen FMR1 mutation among the ID population followed by cascade testing in a remote area. A PCR-based method was used to screen FMR1 expanded alleles using dried blood spot cards in Flores Island, one of the very remote areas in East Indonesia. The screening included 130 males and 81 females from three schools of children with ID. The screening identified three individuals with expanded alleles including two full mutation males and one premutation male. No expanded allele was detected in females. A second blood sample for confirmatory diagnosis was done using Southern blot. Cascade testing in a remote area of Indonesia found a multigenerational family with a large number of cases with FXS. FXS screening of ID populations followed by cascade testing in positive FXS family in a remote area with challenging accessibility is recommended

Group I metabotropic glutamate receptor mediated dynamic immune dysfunction in children with fragile X syndrome.

BackgroundFragile X syndrome (FXS) is the leading cause of inheritable intellectual disability in male children, and is predominantly caused by a single gene mutation resulting in expanded trinucleotide CGG-repeats within the 5' untranslated region of the fragile X mental retardation (FMR1) gene. Reports have suggested the presence of immune dysregulation in FXS with evidence of altered plasma cytokine levels; however, no studies have directly assessed functional cellular immune responses in children with FXS. In order to ascertain if immune dysregulation is present in children with FXS, dynamic cellular responses to immune stimulation were examined.MethodsPeripheral blood mononuclear cells (PBMC) were from male children with FXS (n=27) and from male aged-matched typically developing (TD) controls (n=8). PBMC were cultured for 48 hours in media alone or with lipopolysaccharides (LPS; 1 μg/mL) to stimulate the innate immune response or with phytohemagglutinin (PHA; 8 μg/mL) to stimulate the adaptive T-cell response. Additionally, the group I mGluR agonist, DHPG, was added to cultures to ascertain the role of mGluR signaling in the immune response in subject with FXS. Supernatants were harvested and cytokine levels were assessed using Luminex multiplexing technology.ResultsChildren with FXS displayed similar innate immune response following challenge with LPS alone when compared with TD controls; however, when LPS was added in the presence of a group I mGluR agonist, DHPG, increased immune response were observed in children with FXS for a number of pro-inflammatory cytokines including IL-6 (P=0.02), and IL-12p40 (P<0.01). Following PHA stimulation, with or without DHPG, no significant differences between subjects with FXS and TD were seen.ConclusionsIn unstimulated cultures, subjects with FXS did not display altered dynamic immune response to LPS or PHA alone; however, subjects with FXS showed an altered response to co-current stimulation of LPS and DHPG, such that subjects with FXS failed to inhibit production of pro-inflammatory cytokines, suggesting a role of group I mGluR signaling in innate immune responses in FXS