Genetic short stature

Molecular diagnosis of patients with syndromic short stature identified by trio whole-exome sequencing

Background

Short stature is a complex disorder with phenotypic and genetic heterogeneity. This study aimed to investigate clinical phenotypes and molecular basis of a cohort of patients with short stature.

Methods

Trio whole-exome sequencing (Trio-WES) was performed to explore the genetic aetiology and obtain a molecular diagnosis in twenty Chinese probands with syndromic and isolated short stature.

Results

Of the twenty probands, six (6/20, 30%) patients with syndromic short stature obtained a molecular diagnosis. One novel COMP pathogenic variant c.1359delC, p.N453fs*62 and one LZTR1 likely pathogenic variant c.509G>A, p.R170Q were identified in a patient with short stature and skeletal dysplasia. One novel de novo NAA15 pathogenic variant c.63T>G, p.Y21X and one novel de novo KMT2A pathogenic variant c.3516T>A, p.N1172K was identified in two probands with short stature, intellectual disability and abnormal behaviours, respectively. One patient with short stature, cataract, and muscle weakness had a de novo POLG pathogenic variant c.2863 T>C, p.Y955H. One PHEX pathogenic variant c.1104G>A, p.W368X was identified in a patient with short stature and rickets. Maternal uniparental disomy 7 (mUPD7) was pathogenic in a patient with pre and postnatal growth retardation, wide forehead, triangular face, micrognathia and clinodactyly. Thirteen patients with isolated short stature had negative results.

Conclusion

Trio-WES is an important strategy for identifying genetic variants and UPD in patients with syndromic short stature, in which dual genetic variants are existent in some individuals. It is important to differentiate between syndromic and isolated short stature. Genetic testing has a high yield for syndromic patients but low for isolated patients.

Differential performance regarding the relationship of C3-epi-25(OH)D3 levels and %C3-epi-25(OH)D3 with common pediatric diseases: a case control study

BACKGROUND

Recently, the C3-epimer of 25-hydroxyvitamin D [C3-epi-25(OH)D] has become a topic of interest among 25-hydroxyvitamin D [25(OH)D] metabolites. Although it can lead to an overestimation of vitamin D storage, its relationship with disease occurrence remains controversial, possibly related to the great extent of tracking of 25(OH)D by C3-epi-25(OH)D over time. This study aimed to investigate the differential performance of C3-epi-25(OH)D3 and its percentage [%C3-epi-25(OH)D3] with respect to 20 common paediatric diseases.

METHODS

This study involved 805 healthy children and adolescents and 2962 patients with common paediatric diseases. We investigated sex, age, and seasonal differences in C3-epi-25(OH)D3 and %C3-epi-25(OH)D3 levels; their variations on 20 common paediatric diseases; and their degree of correlation with 25(OH)D3 levels and various diseases.

RESULTS

Among the healthy underage participants, C3-epi-25(OH)D3 and %C3-epi-25(OH)D3 changed similarly, with no sex differences. Moreover, their levels were higher in the infant period than in the other periods (t = 5.329-5.833, t = 4.640-5.711, all Padj < 0.001), and in spring and summer than in autumn and winter (t = 3.495-6.061, t = 3.495-5.658, all Padj < 0.01). Under healthy and disease conditions, C3-epi-25(OH)D3 was positively correlated with 25(OH)D3 (ρ = 0.318 ~ 0.678, all P < 0.017), whereas %C3-epi-25(OH)D3 was not, except in patients with nephrotic syndrome (ρ=-0.393, P = 0.001). Before and after adjusting for 25(OH)D3, the relationship of C3-epi-25(OH)D3 with the diseases was notably different. However, it was almost consistent for %C3-epi-25(OH)D3. Our results indicated that %C3-epi-25(OH)D3 was associated with short stature, nephrotic syndrome, lymphocytic leukaemia, rickets, paediatric malnutrition, and hypovitaminosis D (OR = 0.80 ~ 1.21, all P < 0.05).

CONCLUSIONS

The %C3-epi-25(OH)D3 can correct the properties of C3-epi-25(OH)D3 to better track 25(OH)D3 and may be more suitable for exploring its pathological relevance. Further detailed studies of each disease should be conducted.

Insights into the ANKRD11 variants and short-stature phenotype through literature review and ClinVar database search

Ankyrin repeat domain containing-protein 11 (ANKRD11), a transcriptional factor predominantly localized in the cell nucleus, plays a crucial role in the expression regulation of key genes by recruiting chromatin remodelers and interacting with specific transcriptional repressors or activators during numerous biological processes. Its pathogenic variants are strongly linked to the pathogenesis and progression of multisystem disorder known as KBG syndrome. With the widespread application of high-throughput DNA sequencing technologies in clinical medicine, numerous pathogenic variants in the ANKRD11 gene have been reported. Patients with KBG syndrome usually exhibit a broad phenotypic spectrum with a variable degree of severity, even if having identical variants. In addition to distinctive dental, craniofacial and neurodevelopmental abnormalities, patients often present with skeletal anomalies, particularly postnatal short stature. The relationship between ANKRD11 variants and short stature is not well-understood, with limited knowledge regarding its occurrence rate or underlying biological mechanism involved. This review aims to provide an updated analysis of the molecular spectrum associated with ANKRD11 variants, investigate the prevalence of the short stature among patients harboring these variants, evaluate the efficacy of recombinant human growth hormone in treating children with short stature and ANKRD11 variants, and explore the biological mechanisms underlying short stature from both scientific and clinical perspectives. Our investigation indicated that frameshift and nonsense were the most frequent types in 583 pathogenic or likely pathogenic variants identified in the ANKRD11 gene. Among the 245 KBGS patients with height data, approximately 50% displayed short stature. Most patients showed a positive response to rhGH therapy, although the number of patients receiving treatment was limited. ANKRD11 deficiency potentially disrupts longitudinal bone growth by affecting the orderly differentiation of growth plate chondrocytes. Our review offers crucial insights into the association between ANKRD11 variants and short stature and provides valuable guidance for precise clinical diagnosis and treatment of patients with KBG syndrome.

Deficient or Normal Growth Hormone Secretion in Polish Children with Short Stature: Searching for Clinical Differences

Short stature affects approximately 2.5% of children. Some of them, when diagnosed with growth hormone deficiency (GHD), benefit from recombinant human growth hormone (rhGH) therapy; in others, this treatment is controversial. We aimed to present the clinical characteristics of Polish short stature children in the context of current GHD diagnostic standards, as obtaining more data gives a broader foundation for the potential modifications of diagnostic and therapeutic recommendations. This retrospective analysis was based on a cohort of 277 short stature children divided into two subgroups depending on their peak growth hormone (GH) cutoff level, set at 10 ng/mL: 138 had growth hormone deficiency (GHD) and 137 had normal growth hormone secretion (GHN). These subgroups were then compared based on the extracted clinical data. In the obtained result, no significant differences between the GHD and GHN subgroups were found in any of the variables, including the following: gender distribution, birth weight, bone age delay, height SDS, IGF-1 SDS, vitamin D levels, celiac disease indices, prevalence of hypothyroidism or anemia. As our results point to major clinical similarities between the GHD and GHN children, it seems that distinguishing patients with normal GH secretion from those with deficient GH secretion based on a 10 ng/mL cutoff value might not be clinically relevant.

Vocal Characteristics of Children With Short Stature Before and After Growth Hormone Treatment

OBJECTIVE

To evaluate the vocal characteristics of children with short stature before and 12 months after growth hormone treatment.

MATERIAL AND METHODS

This analytical, observational cohort study included 23 children (age 5-11 years) diagnosed with short stature. Children in the short stature group (SSG) were matched (1:1) for age and sex with children with normal growth (normal stature group; NSG). Participants in the SSG underwent assessments before and 12 months after growth hormone treatment, while those in the NSG underwent the same assessments at baseline and 12 months. The assessments included evaluation of (A) vocal characteristics (history, vocal self-assessment, auditory-perceptual evaluation, and acoustic analysis), (B) anthropometry, (C) bone age, and (D) measurement of insulin-like growth factor-1 (IGF-1) levels.

RESULTS

Children in the SSG had more vocal complaints (P = 0.026) than those in the NSG. The groups were similar in terms of vocal self-assessment and auditory-perceptual evaluation (P = nonsignificant). Results of acoustic analysis were also similar for fundamental frequency (F 0) and perturbation measures (P for both = nonsignificant). F 0 and speech frequency decreased significantly at 12 months in both groups. F1 values were higher at 12 months in the NSG, while F2 values were significantly higher in the baseline evaluation in boys in the SSG. Children in the SSG compared with those in the NSG presented a greater increase in height measurements at 12 months, although the anthropometric means were lower in both evaluations (P < 0.001).

CONCLUSION

Vocal characteristics in children with short stature before and after treatment with growth hormone are comparable to those in children with normal growth.

Association between Height and Functional Outcomes of Patients 6 Months after a Stroke: A Multicenter Prospective Observational Cohort Study

Many physical factors influence post-stroke functional outcomes. However, few studies have examined the influence of height on these outcomes. Here, data from the Korean Stroke Cohort for Functioning and Rehabilitation were used and patients' height was categorized into three groups: short (lower 25%), middle (middle 50%), and tall (upper 25%). Differences in the modified Rankin scale (mRS), functional ambulatory category (FAC), and Korean-translated version of the Modified Barthel Index (K-MBI) scores were analyzed for each group at 6 months post-stroke. A subgroup analysis was conducted based on the initial Fugl-Meyer Assessment (FMA) score. We analyzed functional outcomes in 5296 patients at 6 months post-stroke, adjusting for age and body mass index. The short-height group exhibited higher mRS scores (1.88 ± 0.043), lower FAC scores (3.74 ± 0.045), and lower K-MBI scores (82.83 ± 0.748) than the other height groups (p < 0.05). In the subgroup analysis, except for the very severe FMA group, the short-height group also exhibited worse outcomes in terms of mRS, FAC, and K-MBI scores (p < 0.05). Taken together, the short-height group exhibited worse outcomes related to disability, gait function, and ADLs at 6 months post-stroke.

Longitudinal unraveling: The impact of recombinant human growth hormone on spontaneous brain activity in children with short stature-A resting-state fMRI study

Recombinant human growth hormone (rhGH) is an approved method to improve the growth and ameliorate behavioral issues in children with short stature. However, the data concerning the effects of rhGH treatment on spontaneous brain activity remains unclear. This study included 35 children with short stature, categorized into two groups: the treated group (n = 14) and the untreated group (n = 21). All participants underwent resting-state functional magnetic resonance imaging (rs-fMRI) and neuropsychological assessments at baseline and at the end of a one-year follow-up. The rs-fMRI based amplitude of low frequency fluctuation (ALFF) analysis method was employed to assess spontaneous brain activity. Interaction effects between rhGH and time on ALFF were detected using a mixed-effects analysis. Additionally, Stepwise regression analysis was conducted to investigate the associations between ALFF values and significant clinical indicators. The treated group exhibited significant improvements in height, weight, insulin-like growth factor-1 (IGF-1) levels, insulin-like growth factor binding protein 3 (IGFBP-3) levels, and processing speed index (PSI) when reevaluated from baseline. The interaction effect of rhGH × time was evident in the right putamen (RPUT), where the ALFF value showed a significant increase following rhGH treatment, while also demonstrating a notable positive correlation with height. Moreover, The main effect of time was manifested as a significant decrease in the ALFF value of the left dorsolateral superior frontal gyrus (LSFG) within the untreated group during the follow-up period, concurrently displaying a positive correlation with age. In conclusion, rhGH treatment not only has a positive effect on the growth, cognition, and behavior of children with short stature, but also improves and normalizes spontaneous brain activity.

The Approach to a Child with Dysmorphic Features: What the Pediatrician Should Know

The advancement of genetic knowledge and the discovery of an increasing number of genetic disorders has made the role of the geneticist progressively more complex and fundamental. However, most genetic disorders present during childhood; thus, their early recognition is a challenge for the pediatrician, who will be also involved in the follow-up of these children, often establishing a close relationship with them and their families and becoming a referral figure. In this review, we aim to provide the pediatrician with a general knowledge of the approach to treating a child with a genetic syndrome associated with dysmorphic features. We will discuss the red flags, the most common manifestations, the analytic collection of the family and personal medical history, and the signs that should alert the pediatrician during the physical examination. We will offer an overview of the physical malformations most commonly associated with genetic defects and the way to describe dysmorphic facial features. We will provide hints about some tools that can support the pediatrician in clinical practice and that also represent a useful educational resource, either online or through apps downloaded on a smartphone. Eventually, we will offer an overview of genetic testing, the ethical considerations, the consequences of incidental findings, and the main indications and limitations of the principal technologies.

Role of genetic investigation in the diagnosis of short stature in a cohort of Italian children

BACKGROUND

Short stature (SS) is defined as height more than 2 standard deviations below the mean for age and sex. Hypothyroidism, celiac disease, growth hormone deficiency, hormonal abnormalities, and genetic conditions are among its causes. A wide range of conditions often due to largely unknown genetic variants can elude conventional diagnostic workup.

AIM

We used next-generation sequencing (NGS) to better understand the etiology of SS in a cohort of Italian children.

PATIENTS AND METHODS

The study sample was 125 children with SS of unknown origin referred to our Institute between 2015 and 2021. All had undergone complete auxological and hormonal investigations to exclude common causes of SS. Genetic analysis was performed using a NGS panel of 104 genes. Clinical data were reviewed to clarify the pathogenicity of the variants detected.

RESULTS

In this cohort, 43 potentially causing variants were identified in 38 children. A syndromic genetic condition was diagnosed in 7: Noonan syndrome in 3, Leri-Weill syndrome in 3, and hypochondroplasia in 1. Moreover, 8 benign variants and other 37 like benign variants were found. In 88 children, 179 variants of uncertain significance (VUS) were identified. No variant was found in 16 children.

CONCLUSION

Genetic analysis is a useful tool in the diagnostic workup of patients with SS, in adapting management and treatment, and in identifying syndromes with mild atypical clinical features. The role of VUS should not be underestimated, particularly when multiple VUS with possible mutual worsening effects are present in the same child.

Exome Sequencing Identifies Multiple Genetic Diagnoses in Children with Syndromic Growth Disorders

OBJECTIVE

To evaluate the presence of multiple genetic diagnoses in syndromic growth disorders.

STUDY DESIGN

We carried out a cross-sectional study to evaluate 115 patients with syndromic tall (n = 24) or short stature (n = 91) of unknown cause from a tertiary referral center for growth disorders. Exome sequencing was performed to assess germline single nucleotide, InDel, and copy number variants. All variants were classified according to ACMG/AMP guidelines. The main outcome measured was the frequency of multiple genetic diagnoses in a cohort of children with syndromic growth disorders.

RESULTS

The total diagnostic yield of the cohort was 54.8% (63/115). Six patients had multiple genetic diagnoses (tall stature group = 2; short stature group = 4). The proportion of multiple diagnoses within total cases was 5.2% (6/115), and within solved cases was 9.5% (6/63). No characteristics were significantly more frequent when compared with patients with single or multiple genetic findings. Among patients with multiple diagnoses, 3 had syndromes with overlapping clinical features, and the others had syndromes with distinct phenotypes.

CONCLUSION

Recognition of multiple genetic diagnoses as a possibility in complex cases of syndromic growth disorders opens a new perspective on treatment and genetic counseling for affected patients, defying the medical common sense of trying to fit all findings into one diagnosis.

Diversity and Classification of Genetic Variations in Autism Spectrum Disorder

Autism spectrum disorder (ASD) is a neurodevelopmental condition with symptoms that affect the whole personality and all aspects of life. Although there is a high degree of heterogeneity in both its etiology and its characteristic behavioral patterns, the disorder is well-captured along the autistic triad. Currently, ASD status can be confirmed following an assessment of behavioral features, but there is a growing emphasis on conceptualizing autism as a spectrum, which allows for establishing a diagnosis based on the level of support need, free of discrete categories. Since ASD has a high genetic predominance, the number of genetic variations identified in the background of the condition is increasing exponentially as genetic testing methods are rapidly evolving. However, due to the huge amount of data to be analyzed, grouping the different DNA variations is still challenging. Therefore, in the present review, a multidimensional classification scheme was developed to accommodate most of the currently known genetic variants associated with autism. Genetic variations have been grouped according to six criteria (extent, time of onset, information content, frequency, number of genes involved, inheritance pattern), which are themselves not discrete categories, but form a coherent continuum in line with the autism spectrum approach.

Molecular Diagnostic Yield of Exome Sequencing and Chromosomal Microarray in Short Stature: A Systematic Review and Meta-Analysis

Importance

Currently, the diagnostic yield of exome sequencing (ES) and chromosomal microarray analysis (CMA) for short stature cohorts is uncertain. Despite previous studies reporting the widespread use of ES and CMA, a definitive diagnostic yield has not been established.

Objective

To investigate the diagnostic yield of ES and CMA in short stature.

Data Sources

A systematic literature search was conducted using relevant keywords in 3 databases (PubMed, Embase, and Web of Science) in February 2023.

Study Selection

Eligible studies for meta-analysis were those that had at least 10 participants with short stature who were diagnosed using either ES or CMA and the number of diagnosed patients was reported. Of 5222 identified studies, 20 were eventually included in the study.

Data Extraction and Synthesis

Two independent investigators extracted relevant information from each study, which was then synthesized using proportional meta-analysis to obtain the overall diagnostic yield of ES and CMA.

Main Outcomes and Measures

The primary outcome measure was to determine the overall diagnostic yield of ES and CMA. A subgroup meta-analysis was also performed to assess if the diagnostic yield varied depending on whether ES was used as a first-tier or last-resort test. Additionally, a meta-regression was carried out to investigate how the diagnostic yield varied over time.

Results

Twenty studies were included, comprising 1350 patients with short stature who underwent ES and 1070 patients who completed CMA. The overall diagnostic yield of ES among the cohorts and CMA among the cohorts was found to be 27.1% (95% CI, 18.1%-37.2%) and 13.6% (95% CI, 9.2%-18.7%), respectively. No statistically significant difference was observed between the first-tier (27.8%; 95% CI, 15.7%-41.8%) and last-resort groups (25.6%; 95% CI, 13.6%-39.6%) (P = .83) or in the percentage of positively diagnosed patients over time. No statistically significant difference was observed between the first-tier (27.8%; 95% CI, 15.7%-41.8%) and last-resort groups (25.6%; 95% CI, 13.6%-39.6%) (P = .83) or in the percentage of positively diagnosed patients over time.

Conclusion and Relevance

This systematic review and meta-analysis provides high-level evidence supporting the diagnostic efficacy of ES and CMA in patients with short stature. The findings serve as a solid reference for clinicians when making informed decisions about recommending these genetic tests.

[Syndromic growth retardation caused by impaired function of the ribosomal protein eL13]

Growth retardation for more than 2 SD below the average population or presumed familial target height is classified as a short stature and may be a clinical manifestation of a large number of disorders. The use of the latest methods of molecular genetic analysis in recent years has allowed for a better understanding of the pathogenesis of inherited forms of a short stature. One of the recently discovered mechanisms of this pathology was monoallelic mutations in RPL13 gene, leading to the development of Isidor-Toutain type spondyloepimetaphyseal dysplasia (SEDM). Characteristic phenotypic features for this form are normal birth length, early postnatal growth deficiency, platyspondyly, proximal femoral epiphyseal changes, coxa vara, genu varum. This study presents the clinical and radiological characteristics of the first patient in the Russian -Federation with SEMD caused by a mutation in RPL13 gene.

Case report: Late middle-aged features of FAM111A variant, Kenny-Caffey syndrome type 2-suggestive symptoms during a long follow-up

Kenny-Caffey syndrome type 2 (KCS2) is an extremely rare skeletal disorder involving hypoparathyroidism and short stature. It has an autosomal dominant pattern of inheritance and is caused by variants in the FAM111 trypsin-like peptidase A (FAM111A) gene. This disease is often difficult to diagnose due to a wide range of more common diseases manifesting hypoparathyroidism and short stature. Herein, we present the case of a 56-year-old female patient with idiopathic hypoparathyroidism and a short stature. The patient was treated for these conditions during childhood. Upon re-evaluating the etiology of KCS2, we suspected that the patient had the disorder because of clinical manifestations, such as cortical thickening and medullary stenosis of the bones, and lack of intellectual abnormalities. Genetic testing identified a heterozygous missense variant in the FAM111A gene (p.R569H). Interestingly, the patient also had bilateral sensorineural hearing loss and vestibular dysfunction, which have been rarely described in previous reports of pediatric cases. In KCS2, inner ear dysfunction due to Eustachian tube dysfunction may progress in middle age or later. However, this disease is now being reported in younger patients. Nevertheless, our case may be instructive of how such cases emerge chronically after middle age. Herein, we also provide a literature review of KCS2.

Case report: A novel heterozygous frameshift mutation of ACAN in a Chinese family with short stature and advanced bone age

Short stature (OMIM: 165800) is a common pediatric disorder. Any abnormality in the cartilage formation of the growth plate can cause short stature. Aggrecan, encoded by ACAN, is an important component of the extracellular matrix. Mutations in ACAN have been reported to cause short stature. In the present study, we enrolled a Chinese family with short stature and advanced bone age across three generations. Whole-exome sequencing (WES) was performed on the proband to detect the candidate genes causing short stature in family. A novel heterozygous frameshift mutation (NM_013227.3:c.7230delT; NP_001356197.1: p. Phe2410Leufs*9) of the ACAN gene was confirmed to be a genetic lesion in this family. This variant, which was located in a functional site globular 3 (G3) domain of ACAN and predicted to be deleterious by informatics programs, was co-segregated with the affected family members by performing Sanger sequencing. Literatures review of growth hormone (GH) treatment outcome of all previously reported ACAN patients suggesting that the G3 domain of ACAN may be critical in the development of short stature and growth hormone treatment. These findings not only contribute to the genetic diagnosis and counseling of the family, but will also expand the mutation spectrum of ACAN.

A Case of Growth Hormone Use in Dyggve–Melchior–Clausen Syndrome

Short stature has many causes including genetic disease, skeletal dysplasias, endocrinopathies, familial short stature, and nutritional deficiencies. Recombinant growth hormone (rGH) therapy may be employed to improve stature based on the underlying etiology and growth velocity. Skeletal dysplasia in Dyggve–Melchior–Clausen (DMC) syndrome tends to be progressive, typically with hip involvement, and ultimately leads to bilateral dislocation of the hip joints. Here, we present a pediatric patient with short stature treated with rGH therapy, complicated by the development of debilitating, bilateral hip pain, and found to have DMC syndrome. Our patient had limited range of motion at several joints including the hips after receiving 6 months of rGH therapy. Given the timing of the patient's rGH therapy and the progression of her disease, it is difficult to determine if there were any benefits and instead, is concerning for worsening of her skeletal dysplasia with rGH therapy use. Consequently, patients with severe short stature should have a thorough workup for genetic causes like DMC syndrome, before initiating rGH therapy to determine any potential benefits or harms of treatment.

Analysis of risk factors and construction of a prediction model for short stature in children

BACKGROUND

Short stature in children is an important global health issue. This study aimed to analyze the risk factors associated with short stature and to construct a clinical prediction model and risk classification system for short stature.

METHODS

This cross-sectional study included 12,504 children aged 6-14 years of age from 13 primary and secondary schools in Pingshan District, Shenzhen. A physical examination was performed to measure the height and weight of the children. Questionnaires were used to obtain information about children and their parents, including sex, age, family environment, social environment, maternal conditions during pregnancy, birth and feeding, and lifestyle. The age confounding variable was adjusted through a 1 : 1 propensity score matching (PSM) analysis and 1,076 children were selected for risk factor analysis.

RESULTS

The prevalence of short stature in children aged 6-14 years was 4.3% in the Pingshan District, Shenzhen. The multivariate logistic regression model showed that the influencing factors for short stature were father's height, mother's height, annual family income, father's level of education and parents' concern for their children's height in the future (P < 0.05). Based on the short stature multivariate logistic regression model, a short stature nomogram prediction model was constructed. The area under the ROC curve (AUC) was 0.748, indicating a good degree of discrimination of the nomogram. According to the calibration curve, the Hosmer-Lemesio test value was 0.917, and the model was considered to be accurate. Based on a risk classification system derived from the nomogram prediction model, the total score of the nomogram was 127.5, which is considered the cutoff point to divides all children into low-risk and high-risk groups.

CONCLUSION

This study analyzed the risk factors for short stature in children and constructed a nomogram prediction model and a risk classification system based on these risk factors, as well as providing short stature screening and assessment individually.

Clinical Characteristics of Short-Stature Patients With Collagen Gene Mutation and the Therapeutic Response to rhGH

CONTEXT

Clinical genetic evaluation has been demonstrated as an important tool to elucidate the causes of growth disorders. Genetic defects of collagen formation (the collagenopathies) have been reported to be associated with short stature and skeletal dysplasias. Etiological diagnosis of skeletal abnormality-related short stature is challenging, and less is known about recombinant human growth hormone (rhGH) therapy.

OBJECTIVE

This is a single-center cohort study which aims at exploring the genetic architecture of short-stature children with skeletal abnormalities and evaluating the frequency of collagenopathies to determine their phenotype, including the rhGH treatment response.

PATIENTS AND METHODS

One hundred and six children with short stature and skeletal abnormalities were enrolled who were evaluated by next-generation sequencing (NGS) to detect variants in the skeletal collagen genes including COL1A1, COL1A2, COL2A1, COL9A1, COL9A2, COL9A3, COL10A1, COL11A1, and COL11A2. The results were evaluated using American College of Medical Genetics and Genomics (ACMG) guidelines. Clinical characteristics and rhGH treatment response were summarized.

RESULTS

Twenty-four pathogenic or likely pathogenic variants of collagen genes were found in 26 of 106 (24.5%) short-stature patients with skeletal abnormalities, of which COL2A1 mutations were the most common, accounting for about 57.7%. Other frequent mutations associated with skeletal development include FGFR3, ACAN, NPR2, COMP, and FBN1 in 12.2%, 0.9%, 0.8%, 0.4%, and 0.4%, respectively, resulting in significantly different degrees of short stature. An overview of clinical features of collagenopathies showed growth retardation, skeletal abnormalities, and heterogeneous syndromic abnormalities involving facial, eye, hearing, and cardiac abnormalities. The average height of 9 patients who received rhGH treatment improved from a median of -3.2 ± 0.9 SDS to -2.2 ± 1.3 SDS after 2.8 ± 2.1 years. The most significant height improvement of 2.3 SDS and 1.7 SDS was also seen in two patients who had been treated for more than 6 years.

CONCLUSIONS

A proband-based NGS revealed that distinct genetic architecture underlies short stature in varying degrees and clinical features. Skeletal abnormality-related short stature involving multiple systems should be tested for skeletal collagen gene mutation. Limited rhGH treatment data indicate an improved growth rate and height, and close monitoring of adverse reactions such as scoliosis is required.

Molecular genetic analysis and growth hormone response in patients with syndromic short stature

BACKGROUND

Syndromic short stature is a genetic and phenotypic heterogeneous disorder with multiple causes. This study aims to identify genetic causes in patients with syndromic short stature of unknown cause and evaluate the efficacy of the growth hormone response.

METHODS

Trio-whole-exome sequencing was applied to identify pathogenic gene mutations in seven patents with short stature, multiple malformations, and/or intellectual disability. Whole-genome low-coverage sequencing was also performed to identify copy number variants in three patients with concurrent intellectual disability. Recombinant human growth hormone was administered to improve height in patients with an identified cause of syndromic short stature.

RESULTS

Of the seven patients, three pathogenic/likely pathogenic gene mutations, including one FGFR3 mutation (c.1620C>A p.N540K), one novel GNAS mutation (c.2288C>T p.A763V), and one novel TRPS1 mutation (c.2527_c.2528dupTA p.S843fsX72), were identified in three patients. No copy number variants were identified in the three patients with concurrent intellectual disability. The proband with an FGFR3 mutation, a female 4 and 3/12 years of age, was diagnosed with hypochondroplasia. Long-acting growth hormone improved her height from 85.8 cm [- 5.05 standard deviation (SD)] to 100.4 cm (- 4.02 SD), and her increased height SD score (SDS) was 1.03 after 25 months of treatment. The proband with a GNAS mutation, a female 12 and 9/12 years of age, was diagnosed with pseudohypoparathyroidism Ia. After 14 months of treatment with short-acting growth hormone, her height improved from 139.3 cm (- 2.69 SD) to 145.0 cm (- 2.36 SD), and her increased height SDS was 0.33.

CONCLUSIONS

Trio-whole-exome sequencing was an important approach to confirm genetic disorders in patients with syndromic short stature of unknown etiology. Short-term growth hormone was effective in improving height in patients with hypochondroplasia and pseudohypoparathyroidism Ia.

Retrospective Diagnosis of a Novel ACAN Pathogenic Variant in a Family With Short Stature: A Case Report and Review of the Literature

Short stature is a frequent disorder in the pediatric population and can be caused by multiple factors. In the last few years, the introduction of Next Generation Sequencing (NGS) in the molecular diagnostic workflow led to the discovery of mutations in novel genes causing short stature including heterozygous mutations in ACAN gene. It encodes for aggrecan, a primary proteoglycan component specific for the structure of the cartilage growth plate, articular and intervertebral disc. We report a novel ACAN heterozygous pathogenic variant in a family with idiopathic short stature, early-onset osteoarthritis and osteoarthritis dissecans (SSOAOD). We also performed a literature review summarizing the clinical characteristic of ACAN's patients. The probands are two Caucasian sisters with a family history of short stature and osteoarthritis dissecans. They showed dysmorphic features such as mild midface hypoplasia, brachydactyly and broad thumbs, especially the great toes. The same phenotype was presented in the mother who had had short stature and suffered from intervertebral disc disease. DNA sequencing identified a heterozygous pathogenic variation (c.4390delG p.Val1464Ter) in the sisters, with a maternal inheritance. The nonsense mutation, located on exon 12, results in premature truncation and presumed loss of protein function. In terms of treatment, our patients underwent recombinant human growth hormone replacement therapy, associated with gonadotropin releasing hormone therapy, in order to block early growth cessation and therefore reach a better final height. Our case suggests that SSOAOD ACAN related should be considered in the differential diagnosis of children with autosomal dominant short stature and family history of joints disease.

Clinical Implications of Growth Hormone Deficiency for Oral Health in Children: A Systematic Review

Growth hormone (GH) is involved in the regulation of the postnatal dental and skeletal growth, but its effects on oral health have not been clearly defined. This paper aims to provide a review of current clinical knowledge of dental caries, tooth wear, developmental enamel defects, craniofacial growth and morphology, dental maturation, and tooth eruption in growth hormone deficient (GHD) children. A systematic review was carried out using Scopus, MEDLINE-EbscoHost and Web of Science from 2000 to May 2021. PRISMA guidelines for reporting systematic reviews were followed. All the selected studies involved groups under eighteen years of age, covering a total of 465 GHD patients. The studies that were selected provide reliable evidence for delayed dental maturity and orthodontic disturbances in GHD patients. Data on dental hard tissues pathology are scarce and are limited to occurrences of dental caries. GHD children showed abnormal craniofacial morphology with reduced mandibular dimensions, with a resulting tendency towards Angle's Class II occlusion, which affected up to 31% of patients. Dental age has been shown to be delayed in GHD patients by about 1 to 2 years. Moreover, the risk of dental caries in children with GHD decreases with increasing levels of vitamin D. Hence, further studies would be valuable for evaluating the risk of various oral health problems and to organize targeted dental care for this vulnerable group.

A Polygenic Risk Score to Predict Future Adult Short Stature Among Children

CONTEXT

Adult height is highly heritable, yet no genetic predictor has demonstrated clinical utility compared to mid-parental height.

OBJECTIVE

To develop a polygenic risk score for adult height and evaluate its clinical utility.

DESIGN

A polygenic risk score was constructed based on meta-analysis of genomewide association studies and evaluated on the Avon Longitudinal Study of Parents and Children (ALSPAC) cohort.

SUBJECTS

Participants included 442 599 genotyped White British individuals in the UK Biobank and 941 genotyped child-parent trios of European ancestry in the ALSPAC cohort.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Standing height was measured using stadiometer; Standing height 2 SDs below the sex-specific population average was considered as short stature.

RESULTS

Combined with sex, a polygenic risk score captured 71.1% of the total variance in adult height in the UK Biobank. In the ALSPAC cohort, the polygenic risk score was able to identify children who developed adulthood short stature with an area under the receiver operating characteristic curve (AUROC) of 0.84, which is close to that of mid-parental height. Combining this polygenic risk score with mid-parental height or only one of the child's parent's height could improve the AUROC to at most 0.90. The polygenic risk score could also substitute mid-parental height in age-specific Khamis-Roche height predictors and achieve an equally strong discriminative power in identifying children with a short stature in adulthood.

CONCLUSIONS

A polygenic risk score could be considered as an alternative or adjunct to mid-parental height to improve screening for children at risk of developing short stature in adulthood in European ancestry populations.

Identification and characterization of factors associated with short stature and pre-shortness in Chinese preschool-aged children

OBJECTIVES

We aimed to identify and characterize potential factors, both individually and jointly as a nomogram, associated with short stature and pre-shortness in Chinese preschool-aged children.

METHODS

Total of 9501 children aged 3-6 years were recruited from 30 kindergartens in Beijing and Tangshan from September to December 2020 using a stratified random sampling method. Effect-size estimates are expressed as odds ratio (OR) and 95% CI.

RESULTS

The prevalence of short stature and pre-shortness in preschool-aged children was 3.9% (n = 375) and 13.1% (n = 1616), respectively. Factors simultaneously associated with the significant risk for short stature, pre-shortness and both included BMI, paternal height, maternal height, birth weight, birth height, latter birth order (≥2) and less parental patience to children. Besides, breastfeeding duration (≥12 months) was exclusively associated with pre-shortness (OR, 95% CI, P: 1.16, 1.01 to 1.33, 0.037), and childhood obesity with both short stature (3.45, 2.62 to 4.54, <0.001) and short stature/pre-shortness (1.37, 1.15 to 1.64, <0.001). Modeling of significant factors in nomograms had descent prediction accuracies, with the C-index being 77.0, 70.1 and 71.2% for short stature, pre-shortness and both, respectively (all P < 0.001).

CONCLUSIONS

Our findings indicate the joint contribution of inherited characteristics, nutrition status from the uterus to childhood, and family psychological environment to short stature and pre-shortness in Chinese preschool-aged children. Further validation in other independent groups is warranted.

Exome sequencing reveals genetic architecture in patients with isolated or syndromic short stature

Short stature is among the most common endocrinological disease phenotypes of childhood and may occur as an isolated finding or in conjunction with other clinical manifestations. Although the diagnostic utility of clinical genetic testing in short stature has been implicated, the genetic architecture and the utility of genomic studies such as exome sequencing (ES) in a sizable cohort of patients with short stature have not been investigated systematically. In this study, we recruited 561 individuals with short stature from two centers in China during a 4-year period. We performed ES for all patients and available parents. All patients were retrospectively divided into two groups: an isolated short stature group (group I, n = 257) and an apparently syndromic short stature group (group II, n = 304). Causal variants were identified in 135 of 561 (24.1%) patients. In group I, 29 of 257 (11.3%) of the patients were solved by variants in 24 genes. In group II, 106 of 304 (34.9%) patients were solved by variants in 57 genes. Genes involved in fundamental cellular process played an important role in the genetic architecture of syndromic short stature. Distinct genetic architectures and pathophysiological processes underlie isolated and syndromic short stature.

Identification of contributing predictors for short stature and pre-shortness among 7310 Chinese preschool-aged children

PURPOSES

We aimed to identify the contributing predictors for short stature and pre-shortness in Chinese preschool-aged children, and further to construct nomogram prediction models.

METHODS

A large cross-sectional, kindergarten-based study was conducted during September-November, 2019 in Beijing. Utilizing a stratified random sampling method, total 20 kindergartens with 7310 children with complete data were eligible for analysis.

RESULTS

The prevalence of short stature and pre-shortness was 3.0% (n = 222) and 11.6% (n = 848), respectively. Six contributing predictors were significantly associated with short stature, including parental height (odds ratio, 95% confidence interval, P: 0.773, 0.69-0.86, <0.001), maternal height (0.723, 0.64-0.82, <0.001), birthweight (0.826, 0.74-0.92, 0.001), birth height (0.831, 0.69-1.00, 0.046), children body mass index (1.204, 1.43-1.82, <0.001), and maternal age at menarche (1.614, 1.43-1.82, <0.001). Seven significant contributing predictors were found for pre-shortness, including parental height (0.805, 0.76-0.85, <0.001), maternal height (0.821, 0.77-0.87, <0.001), birthweight (0.881, 0.83-0.93, <0.001), birth height (0.86, 0.78-0.95, 0.003), gestational weight gain (0.851, 0.77-0.94, 0.002), children body mass index (1.142, 1.05-1.24, 0.002), and chronic disease (4.016, 1.66-9.70, 0.002). The nomogram models for short stature and pre-shortness had descent prediction accuracies.

CONCLUSIONS

Our findings indicate that short stature is predominantly determined by inherited and natal factors, and pre-shortness is additionally by modifiable factors.

Prevalence of celiac disease in patients with short stature: A systematic review and meta-analysis

BACKGROUND AND AIM

Short stature is a common extraintestinal manifestation of celiac disease (CeD). We conducted a systematic review and meta-analysis to assess the global prevalence of CeD in patients presenting with short stature.

METHODS

We searched Medline and EMBASE databases for the keywords "celiac disease, coeliac disease, anti-gliadin, tissue transglutaminase antibody, anti-endomysial antibody, short stature and growth retardation." All the studies published from January 1991 to May 2020 were included. Patients without any prior evaluation for short stature were classified as all-cause short stature, while prior evaluated patients, where no cause was found for short stature, were classified as idiopathic short stature. The diagnosis of CeD was based on the European Society for Paediatric Gastroenterology, Hepatology and Nutrition guidelines. A random-effects model was used to pool the data.

RESULTS

Seventeen studies screening 3759 patients (1582 with all-cause short stature and 2177 with idiopathic short stature) were included. The pooled seroprevalence of CeD based on positive anti-tissue transglutaminase antibody and anti-endomysial antibody was 11.2% (95% CI 4.0-21.2%; I²  = 86%) and 9.7% (95% CI 2.7-20.2%; I²  = 95%) for all-cause and idiopathic short stature, respectively. Similarly, pooled prevalence of biopsy-confirmed CeD was 7.4% (95% CI 4.7-10.6%; I²  = 76%) and 11.6% (95% CI 4.1-22.2%; I²  = 97%), for all-cause and idiopathic short stature, respectively. There was an overall severe risk of selection bias and significant heterogeneity in the pooled results.

CONCLUSIONS

Approximately one in 14 patients with all-cause short stature and one in nine patients with idiopathic short stature had biopsy-confirmed CeD. Therefore, evaluation for CeD may be prudent in all patients with short stature.

Association Between Serum Calcium and Phosphorus Levels and Insulin-Like Growth Factor-1 in Chinese Children and Adolescents with Short Stature

Objective

The aim of this study was to investigate the effect of serum calcium and phosphorus levels on the insulin-like growth factor 1 (IGF-1) in Chinese children and adolescents with short stature.

Methods

In this cross-sectional analysis, the clinical data of 747 children with height below –2 SD who were evaluated at the Department of Endocrinology, Affiliated Hospital of Jining Medical University from March 1, 2013, to February 28, 2019, were selected. Anthropometric and biochemical indicators were measured. The relationship between the serum calcium and phosphorus levels and IGF-1 was analysed.

Results

The univariate analysis results showed that serum calcium or phosphorus was significantly associated with IGF-1 SDS. In addition, after adjusting for possible confounding factors, a linear relationship between serum calcium and IGF-1 SDS and a non-linear relationship between serum phosphorus and IGF-1 SDS were observed by smooth curve fitting. The results of the fully adjusted linear regression showed that serum calcium was positively associated with IGF-1 SDS (β 1.07, 95% CI 0.21, 1.92; p = 0.015). In the multivariate piecewise linear regression, when the serum phosphorus level was greater than 1.26 mmol/L, the IGF-1 SDS increased with the increase in serum phosphorus (β 1.92, 95% CI 1.36, 2.48; p < 0.001). However, we did not observe a significant relationship when the serum phosphorus level was less than 1.26 mmol/L (p = 0.223).

Conclusion

This study demonstrated that in Chinese children and adolescents with short stature, circulating calcium and phosphorus concentrations may be associated with the regulation of IGF-1 levels, and this relationship merits further investigation.

Growth-Promoting Therapies May Be Useful In Short Stature Patients With Nonspecific Skeletal Abnormalities Caused By Acan Heterozygous Mutations: Six Chinese Cases And Literature Review

OBJECTIVE

There are numerous reasons for short stature, including mutations in osteochondral development genes. ACAN, one such osteochondral development gene in which heterozygous mutations can cause short stature, has attracted attention from researchers in recent years. Therefore, we analyzed six cases of short stature with heterozygous ACAN mutations and performed a literature review.

METHODS

Clinical information and blood samples from 6 probands and their family members were collected after consent forms were signed. Gene mutations in the probands were detected by whole-exome sequencing. Then, we searched the literature, performed statistical analyses, and summarized the characteristics of all reported cases.

RESULTS

We identified six novel mutations in ACAN: c.1411C>T, c.1817C>A, c.1762C>T, c.2266G>C, c.7469G>A, and c.1733-1G>A. In the literature, more than 200 affected individuals have been diagnosed genetically with a similar condition (height standard deviation score [SDS] -3.14 ± 1.15). Among affected individuals receiving growth-promoting treatment, their height before and after treatment was SDS -2.92±1.07 versus SDS -2.14±1.23 (P<.001). As of July 1, 2019, a total of 57 heterozygous ACAN mutations causing nonsyndromic short stature had been reported, including the six novel mutations found in our study. Approximately half of these mutations can lead to protein truncation.

CONCLUSIONS

This study used clinical and genetic means to examine the relationship between the ACAN gene and short stature. To some extent, clear diagnosis is difficult, since most of these affected individuals' characteristics are not prominent. Growth-promoting therapies may be beneficial for increasing the height of affected patients.

ABBREVIATIONS

AI = aromatase inhibitor; ECM = extracellular matrix; GnRHa = gonadotropin-releasing hormone analogue; IQR = interquartile range; MIM = Mendelian Inheritance in Man; PGHD = partial growth hormone deficiency; rhGH = recombinant human growth hormone; SDS = standard deviation score; SGA = small for gestational age; SGHD = severe growth hormone deficiency.

Individuals with common diseases but with a low polygenic risk score could be prioritized for rare variant screening

PURPOSE

Identifying rare genetic causes of common diseases can improve diagnostic and treatment strategies, but incurs high costs. We tested whether individuals with common disease and low polygenic risk score (PRS) for that disease generated from less expensive genome-wide genotyping data are more likely to carry rare pathogenic variants.

METHODS

We identified patients with one of five common complex diseases among 44,550 individuals who underwent exome sequencing in the UK Biobank. We derived PRS for these five diseases, and identified pathogenic rare variant heterozygotes. We tested whether individuals with disease and low PRS were more likely to carry rare pathogenic variants.

RESULTS

While rare pathogenic variants conferred, at most, 5.18-fold (95% confidence interval [CI]: 2.32-10.13) increased odds of disease, a standard deviation increase in PRS, at most, increased the odds of disease by 5.25-fold (95% CI: 5.06-5.45). Among diseased patients, a standard deviation decrease in the PRS was associated with, at most, 2.82-fold (95% CI: 1.14-7.46) increased odds of identifying rare variant heterozygotes.

CONCLUSION

Rare pathogenic variants were more prevalent among affected patients with a low PRS. Therefore, prioritizing individuals for sequencing who have disease but low PRS may increase the yield of sequencing studies to identify rare variant heterozygotes.

Downregulation of the GHRH/GH/IGF1 axis in a mouse model of Börjeson-Forssman-Lehman syndrome

Börjeson-Forssman-Lehmann syndrome (BFLS) is an intellectual disability and endocrine disorder caused by plant homeodomain finger 6 (PHF6) mutations. Individuals with BFLS present with short stature. We report a mouse model of BFLS, in which deletion of Phf6 causes a proportional reduction in body size compared with control mice. Growth hormone (GH) levels were reduced in the absence of PHF6. Phf6 ^{- /Y} animals displayed a reduction in the expression of the genes encoding GH-releasing hormone (GHRH) in the brain, GH in the pituitary gland and insulin-like growth factor 1 (IGF1) in the liver. Phf6 deletion specifically in the nervous system caused a proportional growth defect, indicating a neuroendocrine contribution to the phenotype. Loss of suppressor of cytokine signaling 2 (SOCS2), a negative regulator of growth hormone signaling partially rescued body size, supporting a reversible deficiency in GH signaling. These results demonstrate that PHF6 regulates the GHRH/GH/IGF1 axis.

Polymorphism of the growth hormone gene GH1 in Polish children and adolescents with short stature

PURPOSE

Short stature in children is a significant medical problem which, without proper diagnosis and treatment, can lead to long-term consequences for physical and psychological health in adult life. Since human height is a polygenic and highly heritable trait, numerous variants in the genes involved in growth-including the growth hormone (GH1) gene-have been identified as causes of short stature.

METHODS

In this study, we performed for the first time molecular analysis of the GH1 gene in a cohort (n = 186) of Polish children and adolescents with short stature, suffering from growth hormone deficiency (GHD) or idiopathic short stature (ISS), and a control cohort (n = 178).

RESULTS

Thirteen SNP variants were identified, including four missense variants, six in 5'UTR, and three in introns. The frequency of minor missense variants was low (<0.02) and similar in the compared cohorts. However, two of these variants, Ala39Val (rs151263636) and Arg42Leu (rs371953554), were found (heterozygote status) in only two GHD patients. These substitutions, according to databases, can potentially be deleterious.

CONCLUSIONS

Mutations of GH1 causing short stature are very rare in the Polish population, but two potentially causative variants need further studies in a larger cohort of GHD patients.

Child development, physiological stress and survival expectancy in prehistoric fisher-hunter-gatherers from the Jabuticabeira II shell mound, South Coast of Brazil

In this study, we shed light on the interdependency of child growth, morbidity and life expectancy in the fisher-hunter-gatherers of the Jabuticabeira II shell mound (1214-830 cal B.C.E. - 118-413 cal C.E.) located at the South Coast of Brazil. We test the underlying causes of heterogeneity in frailty and selective mortality in a population that inhabits a plentiful environment in sedentary settlements. We reconstruct osteobiographies of 41 individuals (23 adults and 18 subadults) using 8 variables, including age-at-death, stature, non-specific stress markers (cribra orbitalia, porotic hyperostosis, periosteal reactions, periapical lesions and linear enamel hypoplasia), as well as weaning patterns based on stable isotope data to examine how stress factors module growth and survival. Our results show that shorter adult statures were linked to higher morbidity around weaning age and higher chances of dying earlier (before 35 years) than taller adult statures. In addition, short juvenile stature was related to physiological stressors and mortality. The adult "survivors" experienced recurrent periods of morbidity during childhood and adulthood, possibly associated with the high parasite load of the ecosystem and dense settlement rather than to malnourishment. An association between early-stress exposure and premature death was not demonstrated in our sample. To explain our data, we propose a new model called "intermittent stress of low lethality". According to this model, individuals are exposed to recurrent stress during the juvenile and adult stages of life, and, nevertheless survive until reproductive age or later with relative success.

Perioperative Outcomes and Complications After Primary Total Hip Arthroplasty in Patients With Disproportionately Short Stature: A Matched Cohort Analysis

BACKGROUND

This study compared (1) perioperative outcomes, (2) postoperative complications, and (3) reoperation rates after primary total hip arthroplasty (THA) between short stature patients and matched control patients.

METHODS

A review of primary THA patients from 2012 to 2017 using an institutional database was conducted. This yielded 12,850 patients of which 108 were shorter than 148 cm. These patients were matched 1:1 by age (P = .527), gender (P = .664), and body mass index (P = .240) to controls. The final study population with minimum 1-year follow-up that was included for analysis comprised 47 patients in the short stature cohort and 57 patients in the control cohort. The following outcomes/complications were compared: operative times, lengths of stay (LOSs), intraoperative fractures, minor complications, 90-day readmissions, and revisions.

RESULTS

Operative times were significantly longer in the short stature cohort than in the matched control cohort (133 ± 65 minutes vs 104 ± 30 minutes, P = .005). In addition, hospital LOS was slightly longer in the short stature group than in the matched control groups (3.2 ± 1.5 days vs 2.6 ± 1.0, P = .017). Rates of intraoperative fractures (P = 1.000), minor complications P = .406), 90-day readmissions (P = .5000), and revision (P = .202) were similar between the short stature and control cohorts.

CONCLUSION

Patients with disproportionately short stature had longer operative times and slight longer LOS. However, complication and readmission rates were similar. Future studies with larger sample sizes are warranted to confirm these findings and further evaluate implant survivorship in this unique THA patient population.

Screening Human Embryos for Polygenic Traits Has Limited Utility

The increasing proportion of variance in human complex traits explained by polygenic scores, along with progress in preimplantation genetic diagnosis, suggests the possibility of screening embryos for traits such as height or cognitive ability. However, the expected outcomes of embryo screening are unclear, which undermines discussion of associated ethical concerns. Here, we use theory, simulations, and real data to evaluate the potential gain of embryo screening, defined as the difference in trait value between the top-scoring embryo and the average embryo. The gain increases very slowly with the number of embryos but more rapidly with the variance explained by the score. Given current technology, the average gain due to screening would be ≈2.5 cm for height and ≈2.5 IQ points for cognitive ability. These mean values are accompanied by wide prediction intervals, and indeed, in large nuclear families, the majority of children top-scoring for height are not the tallest.

Complex Phenotypes: Mechanisms Underlying Variation in Human Stature

PURPOSE OF REVIEW

The goal of the review is to provide a comprehensive overview of the current understanding of the mechanisms underlying variation in human stature.

RECENT FINDINGS

Human height is an anthropometric trait that varies considerably within human populations as well as across the globe. Historically, much research focus was placed on understanding the biology of growth plate chondrocytes and how modifications to core chondrocyte proliferation and differentiation pathways potentially shaped height attainment in normal as well as pathological contexts. Recently, much progress has been made to improve our understanding regarding the mechanisms underlying the normal and pathological range of height variation within as well as between human populations, and today, it is understood to reflect complex interactions among a myriad of genetic, environmental, and evolutionary factors. Indeed, recent improvements in genetics (e.g., GWAS) and breakthroughs in functional genomics (e.g., whole exome sequencing, DNA methylation analysis, ATAC-sequencing, and CRISPR) have shed light on previously unknown pathways/mechanisms governing pathological and common height variation. Additionally, the use of an evolutionary perspective has also revealed important mechanisms that have shaped height variation across the planet. This review provides an overview of the current knowledge of the biological mechanisms underlying height variation by highlighting new research findings on skeletal growth control with an emphasis on previously unknown pathways/mechanisms influencing pathological and common height variation. In this context, this review also discusses how evolutionary forces likely shaped the genomic architecture of height across the globe.

A heterozygous point mutation of the ANKRD11 (c.2579C>T) in a Chinese patient with idiopathic short stature

Background

Pathogenic variants of ANKRD11 have been reported to cause KBG syndrome characterized by short stature, characteristic facial appearance, intellectual disability, macrodontia, and skeletal anomalies. However, the direct clinical relevance of ANKRD11 mutation with short stature is yet unknown.

Methods

Here, we report a Chinese boy with idiopathic short stature (ISS) based on clinical and genetic characteristics. Comprehensive medical evaluations were performed including metabolic studies, endocrine function tests, bone X‐rays, and echocardiography. Whole‐exome and Sanger sequencing was used to detect and confirm genetic mutations associated with short stature in this patient, respectively. The pathogenicity of the variant was further predicted by several in silico prediction tools and repositories of sequence variation. Twenty‐four months follow‐up was performed to observe the growth rate of the patient treated with recombinant human growth hormone (GH).

Results

One heterozygous point mutation (c.2579C>T) was confirmed in the ANKRD11 gene of the patient and inherited from his mother. This mutation site was located within the highly conservative region of ANKRD11 protein and predicted to be possibly damaging in several in silico prediction programs and repositories of sequence variation. Additionally, patient underwent GH replacement therapy for 24 months exhibited good response to the treatment.

Conclusion

A heterozygous point mutation of AKNRD11 gene was identified in a Chinese patient with short stature phenotype. The patient was treated effectively with GH supplementation.

Genetic causes of isolated short stature

Short stature is a common feature, and frequently remains without a specific diagnosis after conventional clinical and laboratorial evaluation. Longitudinal growth is mainly determined by genetic factors, and hundreds of common variants have been associated to height variability among healthy individuals. Although isolated short stature may be caused by the combination of variants, with a deleterious impact on the growth of individuals with polygenic inheritance, recent studies have pointed out some monogenic defects as the cause of the growth disorder observed in nonsyndromic children. The majority of these defects are in genes related to the growth plate cartilage and in the growth hormone (GH) - insulin-like growth factor 1 (IGF-1) axis. Affected patients usually present the mildest spectrum of some forms of skeletal dysplasia, or subtle abnormalities of laboratory tests, suggesting hormonal resistance or insensibility. The lack of specific characteristics, however, does not allow formulation of a definitive diagnosis without the use of broad genetic studies. Thus, molecular genetic studies including panels of genes or exome analysis will become essential in investigating and identifying the causes of isolated short stature in children, with a crucial impact on treatment and follow-up.

A novel GLI2 mutation responsible for congenital hypopituitarism and polymalformation syndrome

OBJECTIVE

We report a novel GLI2 frameshift mutation and describe the phenotypic spectrum of mutations within this gene.

PATIENTS AND METHODS

A male with congenital hypopituitarism and polymalformation syndrome was clinically, biochemically and neuroradiologically characterized. Genetic analysis for congenital hypopituitarism was performed using a targeted NGS custom gene panel.

RESULTS

A heterozygous frameshift mutation, NM_005270.4:c.2125del, p.(Leu709Trpfs*15), was identified in GLI2 exon 12. This mutation has not been previously reported and confirms the diagnosis of Culler-Jones syndrome (MIM #615849).

CONCLUSION

GLI2 mutations should be suspected in the presence of congenital hypopitutarism, characteristic facial abnormalities and polydactyly.