The disclosure features methods for treating hypophosphatasia (HPP) in a patient (e.g., a child or an adolescent having HPP) exhibiting gait impairments or decreased walking ability by administering a soluble alkaline phosphatase (sALP) to the patient and assessing improvement in the gait impairment using a modified Performance-Oriented Mobility Assessment-Gait (mPOMA-G) analysis and score.

Methods of diagnosis and methods of treatment and prevention for autism spectrum disorder are provided using decoy antigens to maternal brain-reactive antibodies.

The present disclosure describes techniques for measuring quantities (e.g., relative frequencies) of sequence end motifs of cell-free DNA fragments in a biological sample of an organism for measuring a property of the sample (e.g., fractional concentration of clinically-relevant DNA) and/or determining a condition of the organism based on such measurements. Different tissue types exhibit different patterns for the relative frequencies of the sequence end motifs. The present disclosure provides various uses for measures of the relative frequencies of sequence end motifs of cell-free DNA, e.g., in mixtures of cell-free DNA from various tissues. DNA from one of such tissue may be referred to as clinically-relevant DNA.

This document provides methods and materials related to genetic variations of developmental disorders. For example, this document provides methods for using such genetic variations to assess susceptibility of developing Autism Spectrum Disorder.

Methods of diagnosis and methods of treatment and prevention for autism spectrum disorder are provided using decoy antigens to maternal brain-reactive antibodies.

Provided are methods for diagnosing a disease in a subject with a previous streptococcal infection by determining the presence or absence of one or more autoantibodies in a biological sample from the subject, wherein the one or more autoantibodies recognize an antigen from a protein selected from the group consisting of ELAVL2, ELAVL3, ELAVL4, Nova-1, Nova-2, Cdr1, Cdr2; and Cdr3. The presence of such autoantibodies is indicative of a positive diagnosis for a post-streptococcal disease such as PANDAS, post-GABHS glomerulonephritis, rheumatic fever, autism and Syndenham's chorea.

Disclosed herein is the use of plasma osteopontin (OPN) levels for diagnosing and predicting the severity and outcomes in traumatic brain injury (TBI), such as adult and pediatric TBI. The disclosed method can be used to diagnose TBI in any subject, such as pediatric, adult, and geriatric subjects. However, the method is particularly useful in pediatric subjects where current methods are insufficient. A particularly useful advantage of the disclosed methods is the ability to diagnose Abusive Head Trauma (AHT) in a pediatric subject.

5-D-fructose dehydrogenase, optionally in combination with invertase and/or maltase and/or glucose isomerase, may be used to treat fructose intolerance. Other embodiments are also disclosed.

Metabolites and signatures (panels) of metabolites are applicable as biomarkers in clinical diagnosis, in particular for neonatal encephalopathy. They are useful tools in differential clinical diagnosis for early detection of brain injury, determination of brain areas affected by the insults and prediction of adverse neurological outcome and may also be applied in diagnosing disease progression and treatment effect. An in vitro method for predicting the likelihood of neonatal encephalopathy of distinct brain areas, identification of affected brain area(s) of neonatal encephalopathy and risk of brain damage and prognosis and neurological outcome due to identification of the type and extent of damage of distinct brain tissues, in particular of hippocampus and/or basal ganglia, is provided.

Early detection of lysosomal storage diseases (LSDs) including Mucopolysaccharidosis Type I (MPS I) and Pompe Disease can greatly improve patient outcome as each disease can be fatal once symptoms emerge. Screening for MPS I and Pompe Disease using biological samples including dried blood spots (DBS), buccal swab, peripheral blood mononuclear cells (PBMCs), or white blood cells (WBCs) is described. The disclosed methods and assays provide a robust way to screen newborns for LSDs. The disclosed methods and assays can also allow rapid prediction of whether a patient with LSD will develop an immune response to enzyme replacement therapy (ERT), thus improving treatment for patients with LSDs. The disclosed methods and assays can also further reduce the number of false positives caused by pseudo deficiency cases of LSD, such as MPS I and Pompe Disease.