Kanya Suphapeetiporn

Chulalongkorn University · Department of Pediatrics

BACKGROUND Thus far, genetic analysis of patients clinically diagnosed with glycogen storage diseases (GSDs) in Thailand has not been reported. AIM To evaluate the clinical and biochemical profiles, molecular analysis and long-term outcomes of Thai children diagnosed with hepatic GSD. METHODS Children aged < 18 years diagnosed with hepatic GSD and...

Background Maple syrup urine disease (MSUD) is a rare autosomal recessive metabolic disorder caused by variants in any of the following genes: BCKDHA , BCKDHB, and DBT gene. Previous reports have highlighted a variety of common causing genes and variants among different ethnic groups affected by MSUD. This study is the first to describe the molecul...

Background The prognosis for relapsed or refractory childhood cancer is approximately 20%. Genetic alterations are one of the significant contributing factors to the prognosis of patients. Objective To investigate the molecular profile of relapsed or refractory childhood cancers in Thai cases. Methods The study design is a descriptive study of pa...

Plectin is a cytoskeletal linker of intermediate filaments, encoded by the PLEC gene. Recently, plectin mutations have been identified in a pair of siblings with progressive familial intrahepatic cholestasis. Here, we reported two unrelated infants with plectinopathy causing cholestatic jaundice with novel variants in the PLEC gene. Trio exome sequ...

Aims Analysis of the F8 gene helps predict the risk of developing factor VIII (FVIII) inhibitors and the depth of phenotype in haemophilia A (HA) patients. Since data in Southeast Asian countries remain scarce, we aim to study F8 variation correlated with HA phenotypes in Thailand. Methods Thai patients with HA were enrolled from seven haemophilia...

Aims Myeloid neoplasms (MNs) with germline predisposition have been recognised as a distinct entity. Emerging evidence suggests that sporadic myelodysplastic syndromes may also harbour undetected germline predispositions. We investigated germline alterations in a cohort of 122 adult Thai MNs. Methods MN patients were recruited and tested for germl...

MRPS23 is a nuclear gene encoding a mitochondrial ribosomal protein. A patient with a mitochondrial disorder was found to carry a variant in MRPS23. More cases are necessary to establish MRPS23 as a mitochondrial disease gene. Of 5134 exomes performed in our center, we identified five independent patients who had similar clinical manifestations and...

Aims Von Willebrand disease (VWD) is an inherited haemostatic disorder with a wide range of bleeding phenotypes based on von Willebrand factor (VWF) levels. Multiple assays including VWF gene analysis are employed to correctly diagnose VWD and its subtypes. However, data on VWF mutations among Southeast Asian populations are lacking. We, therefore,...

Background and Aims Variants in COL4A3, COL4A4 and COL4A5 genes were the most common variants associated with focal segmental glomerulosclerosis (FSGS). Split-luciferase-based trimer formation assay of α345 collagen is a technique that test collagen structure formation by transfect COL4A3/4/5 plasmids into cells. This method was recently used to su...

Disorders of sex development (DSD) can be classified as 46,XX DSD, 46,XY DSD, and sex chromosome DSD. Several underlying causes including associated genes have been reported. Steroidogenic factor-1 is encoded by the NR5A1 gene, a crucial regulator of steroidogenesis in the growth of the adrenal and gonadal tissues. It has been discovered to be resp...

Muscular dystrophies and congenital myopathies are heterogeneous groups of inherited muscular disorders. An accurate diagnosis is challenging due to their complex clinical presentations and genetic heterogeneity. This study aimed to determine the utilisation of exome sequencing (ES) for Thai paediatric patients with muscular disorders. Of 176 paedi...

The spectra of underlying genetic variants for various clinical entities including focal segmental glomerulosclerosis (FSGS) vary among different populations. Here we described the clinical and genetic characteristics of biopsy-proven FSGS patients in Thailand. Patients with FSGS pathology, without secondary causes, were included in our study. Clin...

Objectives Neurodevelopmental disorders (NDDs) are a group of conditions that are clinically and etiologically heterogeneous. Biallelic variants in ACBD6 were previously reported in 7 patients with NDDs. Unfortunately, their clinical information remains very limited with descriptions of only their neurologic and craniofacial features. The purpose o...

A heterozygous nonsense variant in the TIGIT gene was identified in a patient in Thailand who had severe COVID-19, resulting in lower TIGIT expression in T cells. The patient's T cells produced higher levels of cytokines upon stimulation. This mutation causes less-controlled immune responses, which might contribute to COVID-19 severity.

Pharmacoresistant epilepsy presenting during infancy poses both diagnostic and therapeutic challenges. We aim to identify diagnostic yield and treatment implications of exome sequencing (ES) as first-tier genetic testing for infantile-onset pharmacoresistant epilepsy. From June 2016 to December 2020, we enrolled patients with infantile-onset (age ≤...

Background: The signal transducer and activator of transcription 6 (STAT6) signaling pathway plays a central role in allergic inflammation. To date, however, there have been no descriptions of STAT6 gain-of-function variants leading to allergies in humans. Objective: We report a STAT6 gain-of-function variant associated with early-onset multiorg...

Inborn errors of immunity are known to cause not only immunodeficiencies and allergies but also autoimmunity. Leukocyte immunoglobulin-like receptor B1 (LILRB1) is a receptor on leukocytes playing a role in regulating immune responses. No phenotypes have been reported to be caused by germline mutations in LILRB1 . We aimed to identify the causative...

Muscular dystrophies and congenital myopathies are heterogeneous groups of inherited muscular disorders. An accurate diagnosis is challenging due to their complex clinical presentations and genetic heterogeneity. This study aimed to determine the utilization of whole exome sequencing (ES) for Thai paediatric patients with muscular disorders. Of 176...

Introduction The complement decay-accelerating factor (DAF) is encoded by the CD55 gene.¹ Lack of CD55 leads to the excess formation of the membrane attack complex (C5b-9) and overactivation of innate immunity, resulting in cell membrane disruption of various cells such as hematopoietic, endothelial, and epithelial cells.² A case series of CD55 def...

Background Gaucher disease (GD) is a rare lysosomal storage disorder, characterized by hepatosplenomegaly and pancytopenia, with or without neurologic involvement. The disorder is categorized into three phenotypes: GD type 1 or nonneuronopathic GD; GD type 2 or acute neuronopathic GD; and GD type 3 or chronic neuronopathic GD. The purposes of this...

Background Inborn errors of immunity (IEI) comprise more than 400 rare diseases with potential life‐threatening conditions. Clinical manifestations and genetic defects are heterogeneous and diverse among populations. Here, we aimed to characterize the clinical, immunologic, and genetic features of Thai pediatric patients with IEI. The use of whole‐...

To maximize the potential of genomics in medicine, it is essential to establish databases of genomic variants for ethno‐geographic groups that can be used for filtering and prioritizing candidate pathogenic variants. Populations with non‐European ancestry are poorly represented among current genomic variant databases. Here, we report the first high...

Background Gaucher disease (GD is a rare lysosomal storage disorder, characterized by hepatosplenomegaly and pancytopenia, with or without neurologic involvement. The disorder is categorized into three phenotypes: GD type 1 or nonneuronopathic GD; GD type 2 or acute neuronopathic GD; and GD type 3 or chronic neuronopathic GD. The purposes of this s...

Background: Primary immunodeficiency diseases (PIDs) comprise more than 400 rare diseases with potential life-threatening conditions. Clinical manifestations and genetic defects are heterogeneous and diverse among populations. Here, we aimed to characterize the clinical, immunological and genetic features of Thai pediatric patients with PIDs. The u...

Objective: To determine the clinicopathologic features and germline tumor protein p53 (TP53) mutation in children with adrenocortical carcinoma (ACC).Material and Methods: This was a retrospective study. From 2009 to 2018, children with ACC from King Chulalongkorn Memorial Hospital and Phramongkutklao Hospital were enrolled into the study. Clinical...

The use of rapid DNA sequencing technology in severely ill children in developed countries can accurately identify diagnoses and positively impact patient outcomes. This study sought to evaluate the outcome of Thai children and adults with unknown etiologies of critical illnesses with the deployment of rapid whole exome sequencing (rWES) in Thailan...

Chronic kidney disease of unknown etiology (CKDu) has been a problem in renal practice as indefinite diagnosis may lead to inappropriate management. Here, we report a 54-year-old father diagnosed with CKDu at 33 years old and his 8-year-old son with steroid-resistant nephrotic syndrome. Using whole-exome sequencing, both were found to be heterozygo...

Aims Congenital neutropaenia is a rare inherited disorder that mainly affects neutrophils causing severe infection. Mutations in several genes have been implicated in the disease pathogenesis. The genetic defects may vary in different populations, influenced by ethnicity and geographical location. Here we describe the clinical and genotypic charact...

Mitochondrial 3-hydroxy-3 methylglutaryl-CoA synthase-2 deficiency (HMGCS2D) is a rare autosomal recessive inborn error of hepatic ketogenesis, caused by mutations in HMGCS2. As its clinical and laboratory manifestations resemble many other metabolic disorders, HMGCS2D definite diagnosis presents a challenge, frequently requiring molecular tests. O...

Hereditary thrombocytopenia comprises extremely diverse diseases that are difficult to diagnose by phenotypes alone. Definite diagnoses are helpful for patient (Pt) management. To evaluate the role of whole exome sequencing (WES) in these Pts. Cases with unexplained long-standing thrombocytopenia and/or suggestive features were enrolled to the obse...

Background In approximately half of patients with epilepsy and intellectual disability (ID), the cause is unidentified and could be a mutation in a new disease gene. Patient description To determine the discovery of disease-causing mutation in a female patient with epilepsy and ID, we performed trio whole-exome sequencing, reverse transcription po...

Benign adult familial myoclonic epilepsy type 1 (BAFME1) in several Japanese and Chinese families has recently been found to be caused by pentanucleotide repeat expansions in SAMD12. We identified a Thai family with six members affected with BAFME. Microsatellite studies suggested a linkage to the BAFME1 region on chromosome 8q24. Subsequently, lon...

Hemoglobin (Hb) H/Constant Spring disease is a common nondeletional Hb H disease, typically causing a more severe phenotype than the deletional Hb H disease counterpart. Hb Tak, resulting from a dinucleotide insertion (+AC) at codon 146 of beta-globin gene, has an increased oxygen affinity and usually presents with polycythemia. We studied a case o...

Congenital myasthenic syndromes (CMS) comprise a heterogeneous group of genetic disorders of the neuromuscular junction (NMJ). Next generation sequencing (NGS) has been increasingly used for molecular diagnosis in CMS patients. This study aimed to identify the disease-causing variants in Thai patients. We recruited patients with a diagnosis of CMS...

A phenotype of an individual is resulted from an interaction among variants in several genes. Advanced molecular technologies allow us to identify more patients with mutations in more than one genes. Here, we studied a Thai woman with combined clinical features of Marfan (MFS) and Beals (BS) syndromes including frontal bossing, enophthalmos, myopia...

Platelet demand has increased around the world. However, the inadequacy of donors, the risk of transfusion-transmitted infections and associated reactions, and the refractory nature of platelet transfusions are among the limitations of allogeneic platelet transfusions. To alleviate these problems, we propose generating platelets in a laboratory tha...

Background: Genetic tests for primary immunodeficiency disorders (PIDs) are expensive, time-consuming, and not easily accessible in developing countries. Therefore, we studied the feasibility of a customized single nucleotide variant (SNV) microarray that we developed to detect disease-causing variants and copy number variation (CNV) in patients wi...

Background GABAA receptors are ligand-gated chloride channels that regulate inhibitory neurotransmission in the central nervous system. Recently, monoallelic de novo mutations in GABRA5 resulting in altered inhibitory synapses were found in three patients with developmental and epileptic encephalopathy. Patient description: We report on a four-year...

Background Mutations in the ATP1A3 gene are known to be the cause of three distinct neurological syndromes including alternating hemiplegia of childhood (AHC), rapid-onset dystonia parkinsonism (RDP) and cerebellar ataxia, arefexia, pes cavus, optic atrophy and sensorineural hearing impairment (CAPOS). Recent studies have suggested the broader dive...

Craniofrontonasal syndrome (CFNS) is an X-linked disorder caused by mutations in EFNB1. Uncommonly and paradoxically, female patients with CFNS exhibit significantly more severe symptoms than male patients. This is explained by “cellular interference”. Nevertheless, there have been a few reports of male patients severely affected with CFNS due to p...

ATP1A3 related disease is a clinically heterogeneous condition currently classified as alternating hemiplegia of childhood, rapid-onset dystonia-parkinsonism and cerebellar ataxia, areflexia, pes cavus, optic atrophy, and sensorineural hearing loss. Recently, it has become apparent that a remarkably large subgroup is suffering from often difficult-...

Background Macrodactyly is a rare congenital deformity characterized by gigantism of all structures of the digits. Previous reports showed that the mosaic PIK3CA variants were associated with overgrowth syndromes including macrodactyly. Objectives To determine the genetic alteration in a Thai patient with enlarged soft tissue of the left middle an...

Purpose: Our meta-analysis of several ethnic groups (Japanese, Korean, Indian, Brazilian) revealed a significant genome-wide association between cold medicine-related SJS/TEN (CM-SJS/TEN) with severe ocular complications (SOC) and IKZF1 SNPs, suggesting that IKZF1 might be a potential marker for susceptibility to CM-SJS/TEN with SOC. In this study...

Genetic disorders have been shown to co-occur in individual patient. A Thai boy with features of osteogenesis imperfecta (OI) and combined pituitary hormone deficiency (CPHD) was identified. The causative mutations were investigated by whole exome and Sanger sequencing. Pathogenicity and pathomechanism of the variants were studied by luciferase ass...

Epilepsy is a common neurological disorder and identification of its causes is important for a better understanding of its pathogenesis. We previously studied a Thai family with a type of epilepsy, benign adult familial myoclonic epilepsy type 4 (BAFME4), and localized its gene to chromosome 3q26.32-q28. Here, we used single-molecule real-time sequ...

Purpose: To evaluate the association of single nucleotide polymorphisms (SNPs) and the intronic expansion of a trinucleotide repeat (TNR) in the TCF4 gene with Fuchs endothelial corneal dystrophy (FECD) in a Thai population. Methods: In total, 54 Thai FECD patients and 54 controls were recruited for the study. Five SNPs (rs613872, rs2123392, rs1...

Infantile Cushing’s syndrome is potentially found as part of McCune-Albright syndrome (MAS) which is caused by postzygotic somatic mutations of the GNAS gene. MAS is typically characterized by a triad of polyostotic fibrous dysplasia, café-au-lait skin pigmentation, and precocious puberty or other endocrine hyperfunction. Here, we describe a 2-mont...

Bernard–Soulier syndrome (BSS) is a hereditary macrothrombocytopenia caused by defects in the glycoprotein (GP) Ib-IX-V complex. The mechanism of giant platelet formation remains undefined. Currently, megakaryocytes (MKs) can be generated from induced pluripotent stem cells (iPSCs) to study platelet production under pharmacological or genetic manip...

The latent transforming growth factor-beta-binding protein 3 (LTBP3), encoding extracellular matrix proteins, plays a role in skeletal formation. Mutations in LTBP3 have been associated with various types of skeletal dysplasia. We aimed to characterize clinical and molecular features of more patients with mutations in the gene, which may help sugge...

Two clones of human induced pluripotent stem cells (iPSCs) were generated from dermal fibroblasts isolated from a one-year-old Thai patient with X-linked osteogenesis imperfecta. The patient harbored a mutation, p.N459S, in the MBTPS2 gene. The cells were reprogrammed using an integration-free Sendai virus containing KLF4, c-MYC, OCT4 and SOX2. Bot...

ectodermal dysplasia (ED) is a group of hereditary disorders affecting the development of ectodermal organs. There are more than 200 types of ED caused by the mutations in approximately 50 genes.1, 2 Nonetheless, the mutations in some genes have been found in only one family affected with ED. Identification of more families with mutations in the sa...

Intellectual disabilities (ID) are etiologically heterogeneous. Advanced molecular techniques could be helpful in identification of the underlying genetic defects. We aimed to characterize clinical and molecular features of three Thai patients with ID. Patient 1 had ID, hypotonia and lactic acidosis. Patient 2 had ID and growth failure. Patient 3 h...

Objectives: Dentin sialophosphoprotein (DSPP) plays an important role in the mineralization of both dentin and bones. The Dspp null mice developed periodontal diseases. Patients with DSPP mutations have dentinogenesis imperfecta (DGI), but very little is known about their bone characteristics. This study aims to characterize alveolar bone cells of...

Context DAX1 (NR0B1) mutations cause X-linked adrenal hypoplasia congenita (AHC) and hypogonadotropic hypogonadism (HH) in affected males. Affected individuals typically present with early-onset adrenal insufficiency and later develop HH during puberty. Rare cases can present with late-onset adrenal insufficiency or other unusual phenotypes. Objec...

Cerebrospinal fluid flow is crucial for neurodevelopment and homeostasis of the ventricular system of the brain, with localized flow being established by the polarized beating of the ependymal cell (EC) cilia. Here, we report a homozygous one base-pair deletion, c.1193delT (p.Leu398Glnfs*2), in the Kinesin Family Member 6 (KIF6) gene in a child dis...

Ornithine transcarbamylase deficiency (OTCD) is an X-linked urea cycle disorder affecting both males and females. Hemizygous males commonly present with severe hyperammonemic encephalopathy during the neonatal period. Heterozygous females have great phenotypic variability. The majority of female patients can manifest later in life or have unrecogni...

Background The exact cause and mechanisms underlying the pathobiology of autism spectrum disorder (ASD) remain unclear. Dysregulation of long interspersed element-1 (LINE-1) has been reported in the brains of ASD-like mutant mice and ASD brain tissues. However, the role and methylation of LINE-1 in individuals with ASD remain unclear. In this study...

Background: WNT1 mutations cause bone fragility as well as brain anomalies. There are some reported cases of WNT1 mutations with normal cognition. Genotype and phenotype correlation of WNT1 mutations has not been established. Case presentation: Here we present two female siblings with osteogenesis imperfecta (OI) born to a consanguineous couple....

Cerebrospinal fluid flow is crucial for neurodevelopment and homeostasis of the ventricular system of the brain, with localized flow being established by the polarized beating of the ependymal cell (EC) cilia. Here, we report a homozygous one base-pair deletion, c.1193delT (p.Leu398Glnfs*2), in the Kinesin Family Member 6 ( KIF6 ) gene in a child d...

Metaphyseal chondromatosis with D-2-hydroxyglutaric aciduria (MC-HGA) (OMIM 614875) is a severe chondrodysplasia combined with a urinary excretion of D-2-hydroxyglutaric acid. Here, we reported the tenth case of this disease. A 15-year-old boy had symmetric radiolulencies in the metaphyses of the long bones suggesting enchondromatosis and platyspon...

Background Age, race, and analytic method influence levels of blood amino acids, of which reference intervals are required for the diagnosis and management of inherited metabolic disorders. Objectives To establish age-specific reference intervals for blood amino acids in Thai pediatric population measured by liquid chromatography tandem mass spect...

Supplementary Table 1: factors affecting blood amino acids in both univariate and multivariate models. Description: factors that might affect blood amino acids such as age, sex, fasting duration, and dietary intake were analyzed through quantile regression aimed at estimating the conditional median in both univariate and multivariate models. Initia...