This review discusses the epidemiology, pathophysiology, genetic etiology, and management of phenylketonuria (PKU). PKU, an autosomal recessive disease, is an inborn error of phenylalanine (Phe) metabolism caused by pathogenic variants in the phenylalanine hydroxylase (PAH) gene. The prevalence of PKU varies widely among ethnicities and geographic regions, affecting approximately 1 in 24,000 individuals worldwide. Deficiency in the PAH enzyme or, in rare cases, the cofactor tetrahydrobiopterin results in high blood Phe concentrations, causing brain dysfunction. Untreated PKU, also known as PAH deficiency, results in severe and irreversible intellectual disability, epilepsy, behavioral disorders, and clinical features such as acquired microcephaly, seizures, psychological signs, and generalized hypopigmentation of skin (including hair and eyes). Severe phenotypes are classic PKU, and less severe forms of PAH deficiency are moderate PKU, mild PKU, mild hyperphenylalaninaemia (HPA), or benign HPA. Early diagnosis and intervention must start shortly after birth to prevent major cognitive and neurological effects. Dietary treatment, including natural protein restriction and Phe-free supplements, must be used to maintain blood Phe concentrations of 120–360 μmol/L throughout the life span. Additional treatments include the casein glycomacropeptide (GMP), which contains very limited aromatic amino acids and may improve immunological function, and large neutral amino acid (LNAA) supplementation to prevent plasma Phe transport into the brain. The synthetic BH4 analog, sapropterin hydrochloride (i.e., Kuvan®, BioMarin), is another potential treatment that activates residual PAH, thus decreasing Phe concentrations in the blood of PKU patients. Moreover, daily subcutaneous injection of pegylated Phe ammonia-lyase (i.e., pegvaliase; PALYNZIQ®, BioMarin) has promised gene therapy in recent clinical trials, and mRNA approaches are also being studied.

Objective. We evaluated whether the methylenetetrahydrofolate reductase (MTHFR) 677C>T marker influences the risk and severity of Alzheimer's disease (AD) and whether AD is associated with homocysteine, vitamin B12, and cholesterol levels in Egypt.Methods. Forty-three Alzheimer's cases and 32 non-AD controls were genotyped for the 677C>T polymorphism. Clinical characteristics and levels of homocysteine, vitamin B12, and cholesterol were assessed.Results. No significant differences in the frequencies of theMTHFRalleles or genotypes between AD cases and controls (P=0.14) were identified. The 677T mutant allele was significantly overrepresented in AD cases compared to controls (OR=2.22;P=0.03). The 677T/T frequency was three times higher in AD patients than in controls, which could increase plasma homocysteine levels. Severe cases of AD were the most frequent in patients with the T/T genotype (11.6%). The effect of theMTHFRpolymorphism on the risk of AD may be independent of homocysteine, vitamin B12, or even cholesterol levels.Conclusions. TheMTHFR677C>T polymorphism—especially the presence of one copy of the T allele—appears to confer a potential risk for the development of AD. The T/T genotype may contribute to hypercysteinemia as a sensitive marker.

We have updated the dataset of the molecular spectrum of the β-thalassemia (β-thal) in Upper Egypt. Buccal swabs were analyzed from 94 unrelated patients with β-thal major (β-TM) using reverse dot-blot and multiplex amplification refractory mutation system-polymerase chain reaction (ARMS-PCR). The most frequent mutation was IVS-I-110 (G>A) (57%). The IVS-I-110, IVS-I-6 (T>C) and IVS-I-1 (G>A) mutations accounted for 87% of the β-thal anomalies. The codon 39 (C>T) and frameshift codon (FSC) 6 (–A) (GAG>–GG) mutations were only detected in Al-Minya and Qina, respectively. We did not observe the IVS-II-745 (C>G) or –101 (C>T) mutations. Forty-three percent of Upper Egyptians were homozygotes. Our efforts were an important step to complete the mutation map of β-thal in Egypt restricted to Cairo and the Nile Delta regions. This study will help to develop preventative programs for Upper Egyptians. It addressed the genetic drift of the β-thal gene mutations in Africa, Asia, and Europe.

Limited research has assessed associations between schizophrenia and genetic variants of the ankyrin repeat and kinase domain containing 1 (ANKK1) and lymphotoxin-alpha (LTA) genes among individuals of Middle Eastern ancestry. Here we present the first association study investigating theANKK1rs1800497 (T>C) andLTArs909253 (A>G) single-nucleotide polymorphisms in an Egyptian population. Among 120 patients with DSM-IV and PANSS (Positive and Negative Syndrome Scale) assessments of schizophrenia and 100 healthy controls, we determined the genotypes for the polymorphisms using endonuclease digestion of amplified genomic DNA. Results confirmed previous findings from different ethnic populations, in that the rs1800497 and rs909253 polymorphisms were both associated with risk of schizophrenia. Differences between the genotypes of cases and controls were strongly significant (P= 0.0005 for rs1800497 andP= 0.001 for rs909253). The relative risk to schizophrenia was 1.2 (P= 0.01) for the C allele and 0.8 (P= 0.04) for the G allele. The CC, GG, and combined CC/AA genotypes were all more frequent in cases than in controls. These results support an association betweenANKK1andLTAgenetic markers and vulnerability to schizophrenia and show the potential influence of just one copy of the mutant C or G allele in the Egyptian population.

In individuals with Duchenne muscular dystrophy (DMD), exon skipping treatment to restore a wild-type phenotype or correct the frame shift of the mRNA transcript of the dystrophin (DMD) gene are mutation-specific. To explore the molecular characterization of DMD rearrangements and predict the reading frame, we simultaneously screened all 79 DMD gene exons of 45 unrelated male DMD patients using a multiplex ligation-dependent probe amplification (MLPA) assay for deletion/duplication patterns. Multiplex PCR was used to confirm single deletions detected by the MLPA. There was an obvious diagnostic delay, with an extremely statistically significant difference between the age at initial symptoms and the age of clinical evaluation of DMD cases (t value, 10.3; 95% confidence interval 5.95–8.80, P < 0.0001); the mean difference between the two groups was 7.4 years. Overall, we identified 147 intragenic rearrangements: 46.3% deletions and 53.7% duplications. Most of the deletions (92.5%) were between exons 44 and 56, with exon 50 being the most frequently involved (19.1%). Eight new rearrangements, including a mixed deletion/duplication and double duplications, were linked to seven cases with DMD. Of all the cases, 17.8% had duplications with no hot spots. In addition, confirmation of the reading frame hypothesis helped account for new DMD rearrangements in this study. We found that 81% of our Saudi patients would potentially benefit from exon skipping, of which 42.9% had a mutation amenable to skipping of exon 51. Our study could generate considerable data on mutational rearrangements that may promote future experimental therapies in Saudi Arabia.

This review provides descriptive evidence for the potential sociodemographic risk factors of race/ethnicity, younger age, and socioeconomic status, as well as evidence for the immigrant effect in women with breast cancer (BC) across world regions and countries. Using MEDLINE and the Web of Science on epidemiology, incidence/mortality rates, and social determinants, we searched a registry-based dataset and the reference lists of prior reviews of BC women (code C50) from the GLOBOCAN 2022 database and the National Cancer Institute's Surveillance, Epidemiology, and End Results (SEER) program 2024. Globally, 1,959,256 new cases (26.7%) and 495,572 deaths (17.7%) were recorded in women aged <75 years in 2022. The age-standardized incidence rate (ASIR) of BC was the highest among countries with a very high Human Development Index (ASIR, 70.9), a high HDI (ASIR, 44.4), middle-low levels (ASIR, 33.6-32.5), driven by affluent lifestyles and a higher incidence of infectious diseases and infection-associated cancers. Besides, younger BC women are statistically more likely than older ones to have pathogenic germline variants in BC susceptibility genes (BRCA1/2, TP53, PALB2). The descriptive epidemiology presented in this review should be of global value to clinicians, researchers, and policymakers, considering the implementation and implications of population-based BC screening programs.