Untreated Phenylketonuria Research Articles

Vitamin Status in Patients with Phenylketonuria: A Systematic Review and Meta-Analysis.

The published data on the vitamin status of patients with phenylketonuria (PKU) is contradictory; therefore, this systematic review and meta-analysis evaluated the vitamin status of PKU patients. A comprehensive search of multiple databases (PubMed, Web of Sciences, Cochrane, and Scopus) was finished in March 2024. The included studies compared vitamin levels between individuals diagnosed with early-treated PKU and healthy controls while excluding pregnant and lactating women, untreated PKU or hyperphenylalaninemia cases, control groups receiving vitamin supplementation, PKU patients receiving tetrahydrobiopterin or pegvaliase, and conference abstracts. The risk of bias in the included studies was assessed by the Newcastle-Ottawa scale. The effect sizes were expressed as standardised mean differences. The calculation of effect sizes with 95% CI using fixed-effects models and random-effects models was performed. A p-value < 0.05 was considered statistically significant. The study protocol was registered in the PROSPERO database (CRD42024519589). Out of the initially identified 11,086 articles, 24 met the criteria. The total number of participants comprised 770 individuals with PKU and 2387 healthy controls. The meta-analyses of cross-sectional and case-control studies were conducted for vitamin B12, D, A, E, B6 and folate levels. PKU patients demonstrated significantly higher folate levels (random-effects model, SMD: 1.378, 95% CI: 0.436, 2.320, p = 0.004) and 1,25-dihydroxyvitamin D concentrations (random-effects model, SMD: 2.059, 95% CI: 0.250, 3.868, p = 0.026) compared to the controls. There were no significant differences in vitamin A, E, B6, B12 or 25-dihydroxyvitamin D levels. The main limitations of the evidence include a limited number of studies and their heterogeneity and variability in patients' compliance. Our findings suggest that individuals with PKU under nutritional guidance can achieve a vitamin status comparable to that of healthy subjects. Our study provides valuable insights into the nutritional status of PKU patients, but further research is required to confirm these findings and explore additional factors influencing vitamin status in PKU.

The relationship between working memory and anxiety in individuals with early treated phenylketonuria (PKU).

Although early diagnosis and treatment prevent the severe impairments associated with untreated phenylketonuria (PKU), individuals with early treated PKU (ETPKU) nonetheless experience significant neurocognitive and psychological sequelae, including difficulties in working memory (WM) and increased risk of anxiety. The primary objective of the present study was to examine the extent to which anxiety may moderate the relationship between ETPKU and WM performance. A sample of 40 adults with ETPKU and a demographically comparable sample of 40 healthy adults without PKU completed a comprehensive assessment of WM performance and anxiety symptomatology. Data were collected using a variety of remote assessment methods (e.g., web-based neurocognitive tests, semistructured interview, report-based measures). The ETPKU group demonstrated significantly poorer WM performance as compared to the non-PKU group. The groups did not differ significantly in anxiety; however, high anxiety was more common in the ETPKU group (53% of sample) than the non-PKU group (33%). A significant interaction between anxiety, metabolic control (as reflected by Phe levels), and WM performance was observed for the ETPKU group. Individuals with high anxiety and/or high Phe levels (> 360 μmol/L) performed poorer than the non-PKU group. Individuals with low anxiety and relatively low Phe levels (< 360 μmol/L) performed comparably to the non-PKU group. Anxiety was found to moderate the relationship between Phe levels and WM performance in individuals with ETPKU. This finding underscores the importance of accounting for anxiety when evaluating neurocognitive performance in individuals with ETPKU whether for research or clinical purposes. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Phenylketonuria (PKU): Causes, classifications, clinical symptoms, diagnosis and treatment

The autosomal recessive condition phenylketonuria (PKU) is brought on by mutations in the gene that codes for phenylalanine hydroxylase (PAH). Phenylalanine (Phe) builds up in the blood as a result of PAH mutations. Untreated PKU can result in several dangers, including brain damage. Due to factors including enhanced genetic testing and newborn screening, the number of PKU patients is predicted to rise. Therefore, it is necessary to popularize the knowledge of PKU in the society. Additionally, minimizing the occurrence of PKU symptoms is greatly aided by early identification and treatment of PKU. In this context, this review highly summarizes all aspects of knowledge about KPU, focusing on the genetic cause, classification, clinic symptoms, diagnosis, and treatment. Newborn screening and related diagnostic technologies, including the Guthrie test, the McCaman and Robins fluorescence assay, and Tandem mass spectrometry, are introduced in this paper. The dietary measures, PKU Formula, and two effective medications, Kuvan and Palynzio, are involved as well. In addition, state-of-the-art genetic techniques for diagnosis and treatment are also included. With an earlier and more accurate diagnosis, governments around the world should strengthen awareness of PKU and lead to the development of effective diagnostics and therapeutics. Finally, the purpose of this paper is to let more people know about PKU, strive for early detection and treatment, and do everything possible to avoid the occurrence of phenylketonuria symptoms.

Phenylketonuria: A Scoring System for Brain Magnetic Resonance Imaging.

The purpose of our study was to devise a new brain Magnetic Resonance Imaging (MRI) scoring system based on the Loes and modified Loes scores in phenylketonuria (PKU) patients. The brain MRI scans of patients with late diagnosed PKU were evalu- ated retrospectively. Patients' age at diagnosis, age at which diet started, age at MRI, and, blood phenylalanine (Phe) levels at the time point closest to the MRI were recorded. Eleven patients aged from 3 to 28 years were included in the study. The median MRI involvement score was 17 (interquartile range = 3). The most involved white matter areas were the parietooccipital areas. There was a significant (P = .046) correlation between the blood Phe level at the timepoint closest to the imaging and the MRI involvement score. Our study provides insights into the MRI findings and scoring system in PKU patients. We have developed a scoring system based on the widely used Loes and modified Loes scoring systems that can be implemented in clinical practice. Also, our study contributes to the long-forgotten and largely abandoned area-imaging findings in late diagnosed and untreated PKU patients and set the stage for the future research in this field.

Neurological and imaging phenotypes of adults with untreated phenylketonuria: new cases and literature review.

Phenylketonuria (PKU) is the most prevalent congenital disease of amino acid metabolism. Neurological manifestations usually complicate PKU in untreated adult patients. This study describes neurological and imaging phenotypes of adult patients with untreated PKU. We investigated a cohort of 320 unrelated adult patients with suspected genetic leukoencephalopathies using whole-exome sequencing (WES). We analyzed the phenotypic features of adult PKU patients in our cohort and summarized cases reported in the literature. We identified 10 patients in our cohort and 12 patients in the literature, who presented with neurological manifestations and were diagnosed with PKU in adulthood. Approximately 60% of these patients had onset of clinical features in adulthood. The most common neurological symptoms of patients presenting in adulthood were cognitive disturbance and spastic paralysis, followed by vision loss, cerebellar ataxia, weakness of limbs, and seizure. This differed from that of patients presenting with PKU features in childhood, who consistently had mental retardation with various neurological complications emerging during a broad age range. Imaging findings were similar between patients presenting with clinical features in childhood compared with adulthood, comprising symmetric periventricular white matter hyperintense on T2-weighted imaging and diffusion-weighted imaging predominantly in the parietal and occipital lobes. Also, normal brain imaging and diffuse leukoencephalopathies were observed in both patient groups. PKU with clinical features presenting in adulthood is an atypical subtype and should be considered during diagnosis of adults with neurological symptoms and leukoencephalopathy. DWI seems to be most helpful to distinguish patients with PKU. Additionally, we demonstrate that PKU constitutes a part (3.1%) of adult genetic leukoencephalopathies.

Myelin basic protein recovery during PKU mice lifespan and the potential role of microRNAs on its regulation

Untreated phenylketonuria (PKU) patients and PKU animal models show hypomyelination in the central nervous system and white matter damages, which are accompanied by myelin basic protein (MBP) impairment. Despite many assumptions, the primary explanation of the mentioned cerebral outcomes remains elusive. In this study, MBP protein and mRNA expression on brains of wild type (WT) and phenylketonuric (ENU2) mice were analyzed throughout mice lifespan (14-60-180-270-360-540 post-natal days, PND). The results confirmed the low MBP expression at first PND times, while revealed an unprecedented progressive MBP protein expression recovery in aged ENU2 mice. Unexpectedly, unaltered MBP mRNA expression between WT and ENU2 was always observed. Additionally, for the same time intervals, a significant decrease of the phenylalanine concentration in the peripheral blood and brain of ENU2 mice was detected, to date, for the first time. In this scenario, a translational hindrance of MBP during initial and late cerebral development in ENU2 mice was hypothesized, leading to the execution of a microRNA microarray analysis on 60 PND brains, which was followed by a proteomic assay on 60 and 360 PND brains in order to validate in silico miRNA-target predictions. Taken together, miR-218-1-3p, miR-1231-3p and miR-217-5p were considered as the most impactful microRNAs, since a downregulation of their potential targets (MAG, CNTNAP2 and ANLN, respectively) can indirectly lead to a low MBP protein expression. These miRNAs, in addition, follow an opposite expression trend compared to MBP during adulthood, and their target proteins revealed a complete normalization in aged ENU2 mice. In conclusion, these results provide a new perspective on the PKU pathophysiology understanding and on a possible treatment, emphasizing the potential modulating role of differentially expressed microRNAs in MBP expression on PKU brains during PKU mouse lifespan.

GECİKMİŞ TANI İLE TEDAVİ EDİLMEYEN GERİATRİK FENİLKETONÜRİ: ICF TEMELLİ BİR VAKA RAPORU

Purpose: Due to the nature of the phenylketonuria (PKU), it is difficult to categorize these patients' needs in a treatment management. The aim of this study was to evaluate an untreated geriatric PKU patient based on International Classification of Functioning, Disability and Health (ICF).&#x0D; Method: The 72-year-old patient was presented with late-diagnosed and untreated PKU during his lifetime. The body structure and functions of the patient were determined by the Tinetti Scale, Sit-up test for 30-second, The Upper Extremity Index, Barthel Daily Life Activity Scale, Short Form- 36 Quality of Life scales were used to determine activities and limitations. Functional Ambulation Scale and Barthel Index were used for assessing participation.&#x0D; Results: In this case, physical disabilities caused problems in his self-care and participation in life accompanying with cognitive problems, environmental and personal factors are negatively affecting his quality of life.&#x0D; Conclusion: Many aspects of the geriatric PKU's participation in life and the parameters that need to be evaluated remain uncertain. For this reason, we suggest that healthcare professionals working with individuals with geriatric PKU patients might follow the ICF qualifiers and assessment methods as in this case report.

Тетрада фалло: современные данные. Обзор литературы

Tetralogy of Fallot (TоF) is a congenital heart disease that includes ventricular septal defect (VSD), right ventricular outflow tract obstruction, aortic root dextraposition, and right ventricular hypertrophy. TоF occurs in 3 out of 10,000 live births and accounts for 7–10% of all congenital heart defects. The etiology of TоF is multifactorial and may include untreated maternal diabetes, phenylketonuria, and retinoic acid intake. Associated chromosomal abnormalities include trisomies 21, 18, and 13, but recent studies indicate a much higher association with microdeletion of chromosome 22. The familial risk of TоF is 3%. The article presents the results of scientific publications about ToF. In particular, modern and topical issues of genetic predisposition, morphology, diagnosis, indications for surgical treatment, including radical and staged, are considered.

Modeling the cognitive effects of diet discontinuation in adults with phenylketonuria (PKU) using pegvaliase therapy in PAH-deficient mice.

Existing phenylalanine hydroxylase (PAH)-deficient mice strains are useful models of untreated or late-treated human phenylketonuria (PKU), as most contemporary therapies can only be initiated after weaning and the pups have already suffered irreversible consequences of chronic hyperphenylalaninemia (HPA) during early brain development. Therefore, we sought to evaluate whether enzyme substitution therapy with pegvaliase initiated near birth and administered repetitively to C57Bl/6-Pahenu2/enu2 mice would prevent HPA-related behavioral and cognitive deficits and form a model for early-treated PKU. The main results of three reported experiments are: 1) lifelong weekly pegvaliase treatment prevented the cognitive deficits associated with HPA in contrast to persisting deficits in mice treated with pegvaliase only as adults. 2) Cognitive deficits reappear in mice treated with weekly pegvaliase from birth but in which pegvaliase is discontinued at 3 months age. 3) Twice weekly pegvaliase injection also prevented cognitive deficits but again cognitive deficits emerged in early-treated animals following discontinuation of pegvaliase treatment during adulthood, particularly in females. In all studies, pegvaliase treatment was associated with complete correction of brain monoamine neurotransmitter content and with improved overall growth of the mice as measured by body weight. Mean total brain weight however remained low in all PAH deficient mice regardless of treatment. Application of enzyme substitution therapy with pegvaliase, initiated near birth and continued into adulthood, to PAH-deficient Pahenu2/enu2 mice models contemporary early-treated human PKU. This model will be useful for exploring the differential pathophysiologic effects of HPA at different developmental stages of the murine brain.

Frequency of PAH Mutations Among Classic Phenylketon Urea Patients in Mazandaran and Golestan Provinces, North of Iran

Phenylketonuria (PKU) is the most common aminoacidopathy with an autosomal recessive inheritance pattern. A global PKU prevalence is estimated about 6.002 in 100,000 newborns. In Iran, the prevalence of PKU is estimated at about 1 in 4,698, and it shows an increasing trend from north (0.0015%) to south (0.02%) of the country. Untreated PKU causes mental retardation, microcephaly, and seizure. PAH gene mutations located at chromosome 12q23 are responsible for the classical type of this disease. The spectrum of PAH mutations is varied in different ethnicities and different parts of the world. The aim of this study was to investigate the frequency of PAH mutation in the Mazandaran province, which could be useful for genetic counseling and prenatal diagnosis. A total of 66 individuals from 33 families from two provinces (9 families from Golestan and 24 families from Mazandaran) from north of Iran participated in this study. After genomic DNA extraction, PAH gene analysis was carried out using DNA sequencing of both coding and non-coding regions by ABI 3130XL genetic analyzer. Twenty-six different mutations were identified in the PAH gene in this study. Four mutations including IVS10-11 (c.1066-11G>A), c.727C>T (p.Arg243X), c.898G>T (p.Ala300Ser), and c.601C>T (p.His201Tyr) were the most common mutations with 37.48% frequency in Mazandaran province. Most frequent mutations in Golestan province were IVSI0-11 (c.1066-11G>A), c.722delG (p.Arg241fs), c.842C>T (p.Pro281Leu), and IVSII+5 (G>A) with frequency 58.57%. The results from the present study verify heterogeneity of the PAH gene and may help to diagnose tests for carrier detection and prenatal diagnosis of the PKU disease in Iranian population.

Untreated PKU patients without intellectual disability: SHANK gene family as a candidate modifier

Phenylketonuria (PKU) is an inborn error of metabolism caused by variants in the phenylalanine hydroxylase (PAH) gene and it is characterized by excessively high levels of phenylalanine in body fluids. PKU is a paradigm for a genetic disease that can be treated and majority of developed countries have a population-based newborn screening. Thus, the combination of early diagnosis and immediate initiation of treatment has resulted in normal intelligence for treated PKU patients. Although PKU is a monogenic disease, decades of research and clinical practice have shown that the correlation between the genotype and corresponding phenotype is not simple at all. Attempts have been made to discover modifier genes for PKU cognitive phenotype but without any success so far.We conducted whole genome sequencing of 4 subjects from unrelated non-consanguineous families who presented with pathogenic mutations in the PAH gene, high blood phenylalanine concentrations and near-normal cognitive development despite no treatment. We used cross sample analysis to select genes common for more than one patient. Thus, the SHANK gene family emerged as the only relevant gene family with variants detected in 3 of 4 analyzed patients. We detected two novel variants, p.Pro1591Ala in SHANK1 and p.Asp18Asn in SHANK2, as well as SHANK2:p.Gly46Ser, SHANK2:p.Pro1388_Phe1389insLeuPro and SHANK3:p.Pro1716Thr variants that were previously described. Computational analysis indicated that the identified variants do not abolish the function of SHANK proteins. However, changes in posttranslational modifications of SHANK proteins could influence functioning of the glutamatergic synapses, cytoskeleton regulation and contribute to maintaining optimal synaptic density and number of dendritic spines.Our findings are linking SHANK gene family and brain plasticity in PKU for the first time. We hypothesize that variant SHANK proteins maintain optimal synaptic density and number of dendritic spines under high concentrations of phenylalanine and could have protective modifying effect on cognitive development of PKU patients.

In-Silico Screening Compounds of Brassica rapa ssp. chinensis as Potential Inhibitor of Neutral Amino Acid Transporter B0AT1 as an Alternative Phenylketonuria Treatment

Phenylketonuria (PKU) is known as a severe autosomal recessive disease caused by mutations in the expression enzyme, namely the PAH (Phenylalanine Hydroxylase) enzyme that causes the build-up of phenylalanine in the body. Untreated PKU affected brain damage and developmental problems. One of the strategies to reduce phenylalanine in the body is inhibiting B0AT1 activity using carotenoid and terpenoids compounds from Bok choy (Brassica rapa ssp.chinensis). In this study, we evaluated the nine carotenoid and terpenoid compounds from Bok choy as B0AT1 inhibitors. Nine Bok choy compounds, including alpha-carotene, beta-carotene, dimethylallyl pyrophosphate, isopentenyl pyrophosphate, lutein, neoxanthin, violaxanthin, geranylgeranyl diphosphate, and zeaxanthin were downloaded from PubChem database, while the 3D structure of B0AT1 was retrieved from Protein Data Bank RCSB. The compounds and B0AT1 were prepared by PyRx 0.8 version and Discovery Studio ver 21.1.1, then docked with Hex 8.0.0 and analyzed using Discovery Studio ver 21.1.1. This screening implies that three terpenoid compounds dimethylallyl pyrophosphate, isopentenyl pyrophosphate, and geranylgeranyl diphosphate interacts in C domain of B0AT1 while six carotenoid compounds, alpha carotene, beta-carotene, lutein, neoxanthin, violaxanthin, and zeaxanthin interacts in A domain and have possibility to inhibit B0AT1, because it interact with same A domain and have a stronger binding energy than phenylalanine. Alpha carotene has a same residue with phenylalanine, Phe144, making it potentially greater than other compound as inhibitors. Brassica rapa ssp. chinensis is indeed good for consumption by people with phenylketonuria, but it is also necessary to do a further compound screening in other low-phenylalanine diet foods to know which one is better as alternative phenylketonuria treatment.

The rs113883650 variant of SLC7A5 (LAT1) gene may alter brain phenylalanine content in PKU

Functional alteration of the LAT1 amino acid transporter may be responsible for interindividual differences in cerebral phenylalanine content and the lack of intellectual disability in some patients with untreated phenylketonuria. We assessed the effect of the common variant rs113883650 of the SLC7A5 (LAT1) gene on brain phenylalanine content, as measured with use of magnetic resonance spectroscopy. Our results suggest that the presence of this variant could influence the amount of phenylalanine in the brain.

A novel Pah-exon1 deleted murine model of phenylalanine hydroxylase (PAH) deficiency

Phenylalanine hydroxylase (PAH) deficiency, colloquially known as phenylketonuria (PKU), is among the most common inborn errors of metabolism and in the past decade has become a target for the development of novel therapeutics such as gene therapy. PAH deficient mouse models have been key to new treatment development, but all prior existing models natively express liver PAH polypeptide as inactive or partially active PAH monomers, which complicates the experimental assessment of protein expression following therapeutic gene, mRNA, protein, or cell transfer. The mutant PAH monomers are able to form hetero-tetramers with and inhibit the overall holoenzyme activity of wild type PAH monomers produced from a therapeutic vector. Preclinical therapeutic studies would benefit from a PKU model that completely lacks both PAH activity and protein expression in liver. In this study, we employed CRISPR/Cas9-mediated gene editing in fertilized mouse embryos to generate a novel mouse model that lacks exon 1 of the Pah gene. Mice that are homozygous for the Pah exon 1 deletion are viable, severely hyperphenylalaninemic, accurately replicate phenotypic features of untreated human classical PKU and lack any detectable liver PAH activity or protein. This model of classical PKU is ideal for further development of gene and cell biologics to treat PKU.

Minimal Change Disease and Phenylketonuria in an Adult Patient: The Two Sides of Protein Homeostasis.

Phenylketonuria (PKU) is associated with renal impairment so patients with PKU should be periodically screened for proteinuria because podocytopathies, such as minimal change disease (MCD), may be an underlying misdiagnosed condition.MCD in adults demands tight surveillance in case of severe complications including nephrotic syndrome, haematuria and acute kidney injury, and although remission with glucocorticoid therapy is typical, 50-75% of patients will relapse.MCD may be a previously unreported cause of proteinuria and renal involvement in adult patients with PKU, where control of hypertension and moderation of protein overload are essential.

Untreated PKU Patients without Intellectual Disability: What Do They Teach Us?

Phenylketonuria (PKU) management is aimed at preventing neurocognitive and psychosocial dysfunction by keeping plasma phenylalanine concentrations within the recommended target range. It can be questioned, however, whether universal plasma phenylalanine target levels would result in optimal neurocognitive outcomes for all patients, as similar plasma phenylalanine concentrations do not seem to have the same consequences to the brain for each PKU individual. To better understand the inter-individual differences in brain vulnerability to high plasma phenylalanine concentrations, we aimed to identify untreated and/or late-diagnosed PKU patients with near-normal outcome, despite high plasma phenylalanine concentrations, who are still alive. In total, we identified 16 such cases. While intellectual functioning in these patients was relatively unaffected, they often did present other neurological, psychological, and behavioral problems. Thereby, these “unusual” PKU patients show that the classical symptomatology of untreated or late-treated PKU may have to be rewritten. Moreover, these cases show that a lack of intellectual dysfunction despite high plasma phenylalanine concentrations does not necessarily imply that these high phenylalanine concentrations have not been toxic to the brain. Also, these cases may suggest that different mechanisms are involved in PKU pathophysiology, of which the relative importance seems to differ between patients and possibly also with increasing age. Further research should aim to better distinguish PKU patients with respect to their cerebral effects to high plasma phenylalanine concentrations.

Galactosemia.

Galactosemia.

Maternal phenylketonuria in Turkey: outcomes of 71 pregnancies and issues in management.

Untreated phenylketonuria (PKU) in pregnancy causes a severe embryopathy called maternal PKU syndrome. Here, we aimed to assess management issues and pregnancy outcomes in the first published series of PKU pregnancies from the developing world. Data were collected retrospectively in a single center from 71 pregnancies and 45 live births of 32 women with PKU, 11 of whom were diagnosed in adulthood after having an affected child. Microcephaly, intellectual disability, and dysmorphic facies were more prevalent in offspring of untreated than treated pregnancies with classical PKU (100% vs. 0%, 91% vs. 0%, and 73% vs. 23% with p < 0.001, p < 0.001, and p = 0.037, respectively). In treated pregnancies, phenylalanine levels were higher during weeks 6-14 than other periods of gestation (4.38 vs. 3.93, 2.00 and 2.28mg/dl; p < 0.05). Poor compliance correlated with higher phenylalanine levels (ρ = - 0.64, p = 0.019) and fluctuations (ρ = - 0.66, p = 0.014).Conclusion: More frequent phenylalanine measurements during late first trimester are crucial to improve outcomes in treated pregnancies. In order to prevent untreated pregnancies via detecting undiagnosed adults, countries where significantly many women of childbearing age were not screened as newborns may consider pre-pregnancy PKU screening. Microcephaly in the newborn should prompt screening for PKU in the mother. What Is Known •Untreated phenylketonuria during pregnancy causes maternal phenylketonuria syndrome in the newborn. •Effective treatment throughout pregnancy can prevent adverse fetal outcomes. What Is New: •Metabolic control is related to frequency of follow-up and worsens during late first trimester. Closer follow-up during this period may improve metabolic control. •In order to prevent untreated pregnancies, pre-pregnancy phenylketonuria screening may be considered if many women of childbearing age were not screened as newborns.

Detection of sequence mutations in phenylalanine hydroxylase (PAH) gene isolated from Egyptian Phenylketonuria (PKU) patients

Phenylketonuria (PKU) is a relatively common autosomal recessive disorder. The frequency of PKU among Caucasians populations is approximately 1:10.000. PKU is primarily a consequence of a deficiency in phenylalanine hydroxylase (PAH) activity, and un-treated PKU patients develop severe mental retardation. The absence of this enzymatic activity causes disturbances in tyrosine and tryptophan metabolism and diminished formation of catecholamine (dopamine), melanin and serotonin. In the present study, nucleotide sequence mutations were examined and detected in Egyptian phenylketonuria (PKU) patients. Total genomic DNA was extracted from the blood of six PKU patients and specific PAH primers were used to amplify genomic DNA fragments. Nucleotide sequences were processed using Human Splicing Finder software to remove introns and predict cDNAs. Processed cDNA sequences were aligned with reference sequence in the GenBank and healthy control for detection of mutations. The results indicated different sequence polymorphism, which can cause mild or severe mutations. The severity of sequence mutation was correlated with the accumulation of phenylalanine amino acid in the blood. This study is an attempt to early detection of PAH mutations, to control phenylketonuria genetic disorder in Egyptian population.

Hippocampal microglia modifications in C57Bl/6 Pahenu2 and BTBR Pahenu2 phenylketonuria (PKU) mice depend on the genetic background, irrespective of disturbed sleep patterns.

Toxic levels of phenylalanine in blood and brain is a characteristic of (untreated) phenylketonuria (PKU), leading to cognitive deficits in PKU mice. In addition, our recent findings showed that PKU mice (as well as PKU patients) have a disturbed sleep/wake cycle. As a consequence, sleep loss may contribute to cognitive deficits in PKU. Sleep loss has been linked to increased activation of microglia in the hippocampus. In this study, we set out to examine morphological features of the microglia population in the hippocampus of the mouse PKU model, using both the C57Bl/6 and the BTBR strain and their wild-type controls (age 5.3 ± 0.5 months; n = 16 per group, both males and females; n = 8 each). Microglial activation is reflected by retraction and thickening of the dendritic branches and an increase in cell body size of a microglial cell. Such morphological changes of microglia were studied by way of immunohistochemical staining for Iba-1, a microglia-specific calcium binding protein. We measured the number of microglia in seven subregions of the dorsal hippocampus. The level of microglial activation was determined, based on the ratio between the soma size and total cell size (soma size plus the area covered by the dendritic branches). Results showed subtle but statistical significant activation of hippocampal microglia in the C57Bl6, but not in the BTBR, PKU mice when compared with their wild-type controls. Also the total number of microglia was higher in the C57Bl/6 PKU (compared to the wild-type) mouse, but not in the BTBR PKU mouse. It is concluded that the C57Bl/6 PKU mouse has mildly higher microglia activity, which may support rather than hamper hippocampal homeostasis. The results further indicate that high levels of phenylalanine or disturbed sleep patterns do not consequently cause hippocampal microglial activation in the PKU mouse. It is currently unknown why the two PKU mouse strains show these differences in number and activation level of their hippocampal microglia, and to what extent it influences hippocampal functioning. Further scrutinizing the role of microglia functioning in the context of PKU is therefore warranted.