Primordial dwarfism (PD) refers to a group of monogenic genetic disorders characterized by intrauterine growth restriction (IUGR) and severe, persistent postnatal growth retardation. These diseases have been associated with variants of multiple genes whose products are mainly involved in critical cellular biological processes such as maintenance of genomic stability, DNA damage repair, mRNA splicing regulation, and centrosome function. Variants of such genes can directly impair cell proliferation and developmental potential. With the widespread application of molecular genetic technologies such as high-throughput sequencing, significant progress has been made in the research of PD. This article focuses on the major subtypes of PD, including Seckel syndrome, Microcephalic osteodysplastic primordial dwarfism (MOPD) types I/III, MOPD type II, and Meier-Gorlin syndrome. It has systematically summarized the advances in their clinical phenotypic characteristics, pathogenic genes, and molecular mechanisms, with an aim to deepen the understanding of the essence of growth disorders associated with PD.
Humans ; Dwarfism/genetics* ; Microcephaly/genetics* ; Phenotype ; Fetal Growth Retardation/genetics* ; Osteochondrodysplasias/genetics* ; Growth Disorders ; Micrognathism ; Patella/abnormalities* ; Congenital Microtia

OBJECTIVES: To study genotype-phenotype correlations in children with FGFR3 variants and to improve clinical recognition of related disorders. METHODS: Clinical data of 95 patients aged 0-18 years harboring FGFR3 variants, confirmed by whole‑exome sequencing at Shanghai Children's Medical Center from January 2012 to December 2023, were retrospectively reviewed. Detailed phenotypic characterization was performed for 22 patients with achondroplasia (ACH) and 10 with hypochondroplasia (HCH). RESULTS: Among the 95 patients, 52 (55%) had ACH, 24 (25%) had HCH, 9 (9%) had thanatophoric dysplasia, 3 (3%) had syndromic skeletal dysplasia, 2 (2%) had severe achondroplasia with developmental delay and acanthosis nigricans, and 5 (5%) remained unclassified. A previously unreported FGFR3 variant, c.1663G>T, was identified. All 22 ACH patients presented with disproportionate short stature accompanied by limb dysplasia, commonly with macrocephaly, a depressed nasal bridge, bowed legs, and frontal bossing; complications were present in 17 (77%). The 10 HCH patients predominantly exhibited disproportionate short stature with limb dysplasia and depressed nasal bridge. CONCLUSIONS ACH is the most frequent phenotype associated with FGFR3 variants, and missense variants constitute the predominant variant type. The degree of FGFR3 activation appears to correlate with the clinical severity of skeletal dysplasia.
Humans ; Receptor, Fibroblast Growth Factor, Type 3/genetics* ; Child ; Male ; Child, Preschool ; Female ; Infant ; Adolescent ; Dwarfism/genetics* ; Achondroplasia/genetics* ; Lordosis/genetics* ; Infant, Newborn ; Retrospective Studies ; Genetic Association Studies ; Bone and Bones/abnormalities* ; Phenotype ; Limb Deformities, Congenital

OBJECTIVE: To explore the clinical features, genetic characteristics in a child with Miller-McKusick-Malvaux syndrome (3MS) type 1 caused by CUL7 gene variant. METHODS: A child diagnosed with 3MS type 1 at the Children's Hospital Affiliated to Zhengzhou University in February 2021 was selected as the subject of this study. Peripheral blood samples were collected from the child and her parents for genomic DNA extraction. Whole exome sequencing (WES) was performed on the child, and Sanger sequencing was used to validate the candidate variants and analyze their pathogenicity. A literature search was conducted using the keywords "3M syndrome" in the China National Knowledge Infrastructure, Wanfang Data Knowledge Service Platform, and PubMed databases from inception to December 2024. The clinical data of Chinese children with 3MS reported in the literature were summarized. This study was approved by the Medical Ethics Committee of the Children's Hospital Affiliated to Zhengzhou University (Ethics No. 2024-K-020). RESULTS: The child was a 6-year-old and 2-month-old female with facial dysmorphism, skeletal abnormalities, and growth and developmental delay. WES revealed compound heterozygous variants in the CUL7 gene: c.2686G>T (p.E896*) and c.1200delT (p.R401Gfs66). Sanger sequencing confirmed that these two variants were inherited from the child's father and mother, respectively. According to the American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines for the Interpretation of Sequence Variants, c.2686G>T (p.E896) was classified as a pathogenic (PVS1+PM2_Supporting+PM3), and c.1200delT (p.R401Gfs*66) was classified as a likely pathogenic (PVS1+PM2_Supporting). Based on the literature search strategy, 18 relevant articles were identified, including a total of 32 Chinese cases of 3MS, of which 8 were fetuses. A total of 32 Chinese 3MS cases were included in the literature review, of which 8 were fetuses. The majority of these cases carried variants in the CUL7 gene (20/32, 62.5%) and OBSL1 gene (12/32, 37.5%). The main clinical manifestations included intrauterine or postnatal growth and developmental delay (32/32, 100.0%), triangular facies (27/32, 84.3%), and skeletal abnormalities (21/32, 65.6%). CONCLUSION The compound heterozygous variants c.2686G>T (p.E896*) and c.1200delT (p.R401Gfs*66) in the CUL7 gene are likely the genetic cause of 3MS type 1 in the child. For children presenting with facial dysmorphism, skeletal abnormalities, and intrauterine or postnatal growth and developmental delay, 3MS should be considered as a differential diagnosis.
Humans ; Cullin Proteins/genetics* ; Female ; Child ; Limb Deformities, Congenital/genetics* ; Exome Sequencing ; Mutation ; Child, Preschool ; Dwarfism ; Muscle Hypotonia ; Spine/abnormalities*

OBJECTIVE: To analyze the clinical and genetic characteristics of a Chinese pedigree affected with congenital Isolated growth hormone deficiency (IGHD). METHODS: A pedigree presenting with Pituitary stalk interruption syndrome (PSIS) (including the proband, his two younger sisters and both parents) who had visited the Capital Institute of Pediatrics Affiliated to Capital Medical University in September 2020 was selected as the study subject. Clinical data were collected. Peripheral blood samples were collected from the proband and his family members. Following the extraction of genomic DNA, whole-exome sequencing (WES) was carried out, and candidate variants were validated by Sanger sequencing. The pathogenicity of the candidate variants was classified based on guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of the Institute Pediatrics of Capital Medical University (Ethics No.: SHERLL2025033). RESULTS: The proband and one younger sister (Ⅱ3) presented with growth retardation, short stature, and a doll-like facies. Another younger sister (Ⅱ2) and both parents had normal heights and appearance. Sanger sequencing confirmed that the proband and his younger sister (Ⅱ3) both harbored compound heterozygous variants of the GHRHR gene, namely c.776C>A (p.T259K) and c.1166G>A (p.R389Q). The other younger sister (Ⅱ2) and the parents were heterozygous carriers. The c.1166G>A (p.R389Q) variant was unreported previously. Based on the guidelines from the ACMG, it was classified as variant of uncertain significance (PM2_Supporting+BP4). Bioinformatics analysis indicated a deleterious effect on the protein function. CONCLUSION Variants of the GHRHR gene probably underlay the pathogenesis of IGHD in this pedigree. Above finding has provided a basis for the clinical diagnosis and genetic counseling for this family.
Child ; Female ; Humans ; Male ; China ; Dwarfism, Pituitary/genetics* ; Exome Sequencing ; Human Growth Hormone/deficiency* ; Mutation ; Pedigree ; Receptors, Neuropeptide/genetics* ; Receptors, Pituitary Hormone-Regulating Hormone/genetics* ; East Asian People/genetics*

Achondroplasia is a rare genetic disorder that affects endochondral ossification resulting in decreased linear bone growth. It is a form of primary skeletal dysplasia that accounts for more than 90% of disproportionate short stature in humans with an incidence of approximately 1 in 15,000–1 in 40,000 live births. These patients present with a characteristic craniofacial appearance along with musculoskeletal, respiratory, and cardiac abnormalities that, when superimposed with the physiological changes of pregnancy, may complicate anesthetic management. The paucity of evidence-based recommendations and protocols for the anesthetic management of parturients with achondroplasia for cesarean delivery poses a challenge in the choice of anesthesia and warrant special anesthetic considerations. Knowing the intricate relationship between the existing anatomical and physiological changes in achondroplasia and pregnancy is crucial for favorable patient outcomes. This is a case report of a 26-year-old primipara with achondroplasia who had a cesarean delivery for malpresentation under spinal anesthesia.

Achondroplasia is a rare genetic disorder that affects endochondral ossification resulting in decreased linear bone growth. It is a form of primary skeletal dysplasia that accounts for more than 90% of disproportionate short stature in humans with an incidence of approximately 1 in 15,000–1 in 40,000 live births. These patients present with a characteristic craniofacial appearance along with musculoskeletal, respiratory, and cardiac abnormalities that, when superimposed with the physiological changes of pregnancy, may complicate anesthetic management. The paucity of evidence-based recommendations and protocols for the anesthetic management of parturients with achondroplasia for cesarean delivery poses a challenge in the choice of anesthesia and warrant special anesthetic considerations. Knowing the intricate relationship between the existing anatomical and physiological changes in achondroplasia and pregnancy is crucial for favorable patient outcomes. This is a case report of a 26-year-old primipara with achondroplasia who had a cesarean delivery for malpresentation under spinal anesthesia.

Achondroplasia is a rare genetic disorder that affects endochondral ossification resulting in decreased linear bone growth. It is a form of primary skeletal dysplasia that accounts for more than 90% of disproportionate short stature in humans with an incidence of approximately 1 in 15,000–1 in 40,000 live births. These patients present with a characteristic craniofacial appearance along with musculoskeletal, respiratory, and cardiac abnormalities that, when superimposed with the physiological changes of pregnancy, may complicate anesthetic management. The paucity of evidence-based recommendations and protocols for the anesthetic management of parturients with achondroplasia for cesarean delivery poses a challenge in the choice of anesthesia and warrant special anesthetic considerations. Knowing the intricate relationship between the existing anatomical and physiological changes in achondroplasia and pregnancy is crucial for favorable patient outcomes. This is a case report of a 26-year-old primipara with achondroplasia who had a cesarean delivery for malpresentation under spinal anesthesia.

OBJECTIVE: To analyze the genetic characteristics of a child with Meier-Gorlin syndrome (MGS) due to a homozygous variant of the ORC6 gene. METHODS: A child who was admitted to the Children's Hospital Affiliated to Soochow University on March 25, 2019 due to growth retardation was selected as the study subject. Clinical data of the child was collected. Whole exome sequencing was carried out for the child. Candidate variant was validated by Sanger sequencing and bioinformatic analysis. RESULTS: The child, a 8-year-and-3-month-old male, has featured short stature, small ears, bilateral cryptorchidism and patellar dysplasia. His parents were of first cousins. The child was found to harbor a homozygous c.712A>T (p.K238*) missense variant of the ORC6 gene, which may lead to premature termination of protein translation. Sanger sequencing confirmed that both of his parents were heterozygous carriers. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was classified as pathogenic (PVS1_Moderate+PM2_Supporting+PM3+PP3+PP4). CONCLUSION The homozygous c.712A>T (p.K238*) variant probably underlay the MGS in this child.
Humans ; Infant ; Male ; Computational Biology ; Congenital Microtia/genetics* ; Dwarfism/genetics* ; Growth Disorders/genetics* ; Origin Recognition Complex/genetics*

OBJECTIVE: To explore the clinical and genetic characteristics of a boy with isolated maternal uniparental disomy of chromosome 20 [UPD(20)mat]. METHODS: A child who was admitted to the Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology on April 8,2021. was selected as the study subject. Phenotypic and endocrinological findings of the child were retrospectively analyzed. Whole exome sequencing (WES) and methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) were carried out for detecting the UPD sequences and copy number variations. Both of his parents were verified by Sanger sequencing. Relevant literature was systematically reviewed. RESULTS: The child, a 3-year-and-8-month-old boy born to a 41-year-old mother by Cesarean delivery at 36⁺² gestational weeks due to oligohydramia, had a birth weight of 2 300 g and length of 46 cm. He was admitted to the NICU for feeding difficulties which had persisted despite of clinical management. At the age of 3.75, he had a height of 92.5 cm (< 3rd percentile; 25th ~ 50th percentile at 2.5 years) and a weight of 10.8 kg (< 3rd percentile; 50th percentile at 15 months). He had also presented with growth retardation, short stature, attention deficit and hyperactivity disorder (ADHD), mild mental retardation, and speech and language development disorders. He had simian creases in both hands but no additional dysmorphic signs, and his motor development was normal. Serum insulin, thyroid-stimulating hormone, and insulin growth factor binding protein 3 levels were within the normal ranges, though insulin growth factor-1 (IGF-1) was slightly decreased. Since that time he had continuously used atomoxetine hydrochloride capsules to control his ADHD. WES and MS-MLPA revealed the existence of UPD (20)mat. CONCLUSION The UPD(20)mat syndrome is characterized by feeding difficulties, growth retardation and short stature. The child in our case has been accompanied by ADHD and speech and language development disorders, which required long-term treatment. For women with advanced maternal age and suggestive phenotypes, genetic testing and counseling should be conducted.
Male ; Pregnancy ; Humans ; Child ; Female ; Infant ; Adult ; Chromosomes, Human, Pair 20 ; DNA Copy Number Variations ; Retrospective Studies ; Uniparental Disomy/genetics* ; Atomoxetine Hydrochloride ; Dwarfism ; Intercellular Signaling Peptides and Proteins ; Language Development Disorders ; Growth Disorders ; Insulins

Short stature is a common physical developmental abnormality in children. Without timely and accurate diagnosis, as well as early intervention, it can impose a heavy burden on the children and their families. There are numerous causes for short stature, and the diagnostic process essentially involves identifying its underlying causes. Based on a thorough understanding of the regular patterns of child physical development and the characteristics of individuals at high risk of short stature, a scientific definition of short stature needs to be established, along with standardized diagnostic and treatment protocols, to achieve early diagnosis or referral for short stature. Furthermore, it is necessary to enhance scientific awareness of short stature among parents and primary care pediatricians, in order to avoid over-treatment, missed diagnoses, and misdiagnoses arising from "misconceptions", and to improve the scientific assessment of short stature.
Humans ; Child ; Dwarfism/diagnosis* ; Child Development ; Parents ; Body Height ; Growth Disorders/etiology*