Clinical experience of next generation sequencing based expanded carrier screening in high-risk couples from a tertiary healthcare center in Pakistan.

Introduction: Carrier screening for genetic conditions has long been a part of preconception and prenatal care. While the use of expanded carrier screening (ECS) is widely common in HICs (high income countries), the clinical actionability of ECS in LMICs (low middle income countries) with high consanguineous unions is not well-understood.

Method: Retrospective chart review of couples who presented to the Prenatal Genetics Clinic at Aga Khan University Hospital, between the period of June 2018 and November 2022.

Evaluation of the clinical, biochemical, and genetic presentation of neonatal and adult-onset 5,10-methylene tetrahydrofolate reductase (MTHFR) deficiency in patients from Pakistan.

Objectives: To study the biochemical, clinical and molecular characteristics of 5,10- methylenetetrahydrofolate reductase (MTHFR) deficiency in Pakistani patients from a single center.

Methods: Medical charts, urine organic acid chromatograms, plasma methionine and Hcys levels, and molecular testing results of gene of patients presenting at the Biochemical Genetics Clinic, AKUH from 2016 to 2022 were reviewed.

Results: Neonatal MTHFR deficiency was found in five patients.

The spectrum of hereditary neuromuscular disorders in the Pakistani population.

Hereditary neuromuscular disorders (NMDs) are a broad group of clinically heterogeneous disorders with varying inheritance patterns, that are associated with over 500 implicated genes. In the context of a highly consanguineous Pakistani population, we expect that autosomal recessive NMDs may have a higher prevalence compared with patients of European descent. This is the first study to offer a detailed description of the spectrum of genes causing hereditary NMDs in the Pakistani population using NGS testing.

Experience in prenatal genetic testing and reproductive decision-making for monogenic disorders from a single tertiary care genetics clinic in a low-middle income country.

Objectives: Explore health-care seeking behaviour among couples with pregnancies at-risk of monogenic disorders and compare time duration for obtaining Prenatal Genetic Test (PGT) results based on (i) amniocentesis and Chorionic Villus Sampling (CVS) (ii) in-house testing and out-sourced testing. Report the spectrum of monogenic disorders in our cohort.

Methods: Medical records of women consulting prenatal genetic counselling clinic at Aga Khan University Hospital, Karachi from December-2015 to March-2021 with history of miscarriage or a monogenic disorder in previous children were reviewed.

L-2-hydroxyglutaric aciduria - review of literature and case series.

Unlabelled: L-2-hydroxyglutaric aciduria (L2HGA) is an autosomal recessive, slowly progressive neurodegenerative disease characterized by psychomotor delay and cerebellar dysfunction. The biochemical hallmark is increased concentrations of L2HG in body fluids. Brain MRI exhibits characteristic centripetal extension of the white matter involvement that differentiates it from other leukodystrophies.

Perspective on newborn screening (NBS): Evidence sharing on conditions to be included in NBS in Pakistan.

Newborn screening aims at detecting treatable disorders early so that the treatment can be initiated to prevent mortality and morbidity. Such programmes are well established in most developed countries, and all newborns are screened for selected metabolic, endocrine and other disorders based on disease epidemiology, testing and treatment availability, efficiency and cost-effectiveness. Even in developing countries, such screening programmes are initiated using heel prick capillary blood collected on filter paper.

Blue rubber bleb nevus syndrome in a Pakistani child: A case report and regional literature review.

Blue rubber bleb nevus syndrome (BRBNS) is a rare disorder in which there is development of multiple venous malformations and haemangiomas in the skin and visceral organs. The lesions mostly involve the skin and gastrointestinal systems but other organs, including the liver, muscles, and the central nervous system, can also be involved. If untreated, affected individuals develop severe anaemia.

Musculoskeletal manifestations in Alkaptonuria: A cross-sectional study.

This study aimed to determine the patient characteristics and clinical presentation of Alkaptonuria cases reported by the Biochemical Genetics Lab.An observational study was conducted at the Biochemical Genetics Lab. Alkaptonuria patients were diagnosed based on the homogentisic acid peak in urine and their demographics and clinical data collected from to 2013 to 2019.

Maple syrup urine disease: magnetic resonance imaging findings in three patients.

Maple syrup urine disease (MSUD) is an autosomal recessive inherited metabolic disorder, caused by branched-chain alpha-ketoacid dehydrogenase (BCKD) deficiency, leading to toxic accumulation of branched-chain amino acids (BCAAs) including leucine, isoleucine and valine and their corresponding a-ketoacids. The diagnosis of MSUD is based on elevated BCAAs and allo-isoleucine in plasma, and branched-chain hydroxyacids and ketoacids in urine. The identification of alloisoleucine >5 µmol/L is considered pathognomonic.

PIGG variant pathogenicity assessment reveals characteristic features within 19 families.

Purpose: Phosphatidylinositol Glycan Anchor Biosynthesis, class G (PIGG) is an ethanolamine phosphate transferase catalyzing the modification of glycosylphosphatidylinositol (GPI). GPI serves as an anchor on the cell membrane for surface proteins called GPI-anchored proteins (GPI-APs). Pathogenic variants in genes involved in the biosynthesis of GPI cause inherited GPI deficiency (IGD), which still needs to be further characterized.

Clinico-Pathological and Molecular Spectrum of Biotinidase Deficiency- Experience from a Lower Middle-Income Country.

Background: The aim of this study was to evaluate the clinical, biochemical, and molecular analysis of Pakistani patients with biotinidase deficiency (BD).

Methods: Medical charts, urine organic acid (UOA) chromatograms, and biotinidase (BTD) enzyme activity of 113 suspected BD cases and BTD gene results of BTD enzyme deficient patients presenting at the Biochemical Genetics Clinic, AKUH from January 2010 to December 2019 were reviewed. Details were collected on a prestructured questionnaire.

A pathogenic UFSP2 variant in an autosomal recessive form of pediatric neurodevelopmental anomalies and epilepsy.

Purpose: Neurodevelopmental disabilities are common and genetically heterogeneous. We identified a homozygous variant in the gene encoding UFM1-specific peptidase 2 (UFSP2), which participates in the UFMylation pathway of protein modification. UFSP2 variants are implicated in autosomal dominant skeletal dysplasias, but not neurodevelopmental disorders.

Vitamin B6-dependent epilepsy due to pyridoxal phosphate-binding protein (PLPBP) defect - First case report from Pakistan and review of literature.

Introduction: The Vitamin B6-dependent epilepsies are a heterogeneous group of autosomal recessive disorders usually characterized by neonatal onset seizures responsive to treatment with vitamin B6 available as pyridoxine (PN) or as the biologically active form pyridoxal 5-phosphate (PLP). The vitamin B6-dependent epilepsies are caused by mutations in at least five different genes involved in B6 metabolism. A literature review revealed that only 30 patients with vitamin B6-dependent epilepsy caused by mutation have been reported worldwide.

Glycogen storage diseases-time to flip the outdated diagnostic approach centered on liver biopsy with the molecular testing.

The glycogen storage diseases (GSDs) are a group of inherited metabolic disorders that result from a defect in any one of several enzymes required for either glycogen synthesis or glycogen degradation. The traditional diagnostic approach is based on the invasive hepatic or muscle biopsies, which are neither cost effective nor convenient. Molecular (gene testing) has emerged over the course of past few years as a robust alternative diagnostic tool, which not only confirms the diagnosis of GSDs but also clearly differentiates the types of GSDs allowing the initiation of the type-specific appropriate treatment for the particular type of GSDs.

Retrospective Study of Patients with Hyperphenylalaninemia- Experience from a Tertiary Care Center in Pakistan.

Objective: To assess the clinical and biochemical features as well as outcome of hyperphenylalaninemia patients.

Methods: The descriptive retrospective study was conducted at the Aga Khan University Hospital, Karachi, and comprised data from January 2013 to February 2017 of plasma amino acid analysed at the Biochemical Genetic Laboratory of patients with phenylalanine levels >120 umol/L. Medical charts of patients registered with the Metabolic Clinics were reviewed, while outside referrals were contacted by telephone to collect data on a pre-structured questionnaire.

Inherited metabolic disorders presenting as hypoxic ischaemic encephalopathy: A case series of patients presenting at a tertiary care hospital in Pakistan.

In spite of the efforts and interventions by the Government of Pakistan and The World Health Organization, the neonatal mortality in Pakistan has declined by only 0.9% as compared to the global average decline of 2.1% between 2000 and 2010.

Ethical issues in managing Lysosomal storage disorders in children in low and middle income countries.

The lysosomal storage diseases are a group of rare, inherited metabolic diseases affecting about 1 in 7000 to 8000 people. In recent years, the introduction of enzyme replacement therapy, substrate reduction therapy and small molecule therapy, has changed the natural course of this otherwise progressive group of disorders leading to severe morbidity and early mortality. These treatment options, however, are extremely expensive and are needed for life thus presenting an economical as well as ethical challenge to the affected families and the health care system of a country.