FGD1-related Aarskog-Scott syndrome: Identification of four novel variations and a literature review of clinical and molecular aspects.

Patients with Aarskog-Scott syndrome (AAS) have short stature, facial anomalies, skeletal deformities, and genitourinary malformations. FYVE, RhoGEF, and PH domain-containing 1 (FGD1) is the only known causative gene of AAS. However, the diagnosis of AAS remains difficult, and specific treatments are still absent. Patients suspected with AAS were recruited, and clinical information was collected. Genetic testing and functional analysis were carried out for the diagnosis. By literature review, we summarized the clinical and genetic characteristics of FGD1-related AAS and analyzed the genotype-phenotype correlation. Five patients were recruited, and four novel FGD1 variants were identified. The diagnosis of AAS was confirmed by genetic analysis and functional study. Three patients treated with growth hormone showed improved heights during the follow-up period. By literature review, clinical features of AAS patients with FGD1 variants were summarized. Regarding FGD1 variations, substitutions were the most common form, and among them, missense variants were the most frequent. Moreover, we found patients with drastic variants showed higher incidences of foot and genitourinary malformations. Missense variants in DH domain were related to a lower incidence of cryptorchidism.   Conclusion: We reported four novel pathogenic FGD1 variations in AAS patients and confirmed the efficacy and safety of growth hormone treatment in FGD1-related AAS patients with growth hormone deficiency. Additionally, our literature review suggested the crucial role of DH domain in FGD1 function. What is Known: • Aarskog-Scott syndrome is a rare genetic disease, and the only known cause is the variant in FGD1 gene. The typical clinical manifestations of AAS include facial, skeletal, and urogenital deformities and short stature. What is New: • We reported four novel FGD1 variants and reported the treatment of growth hormone in FGD1-related AAS patients. Our genotype-phenotype correlation analysis suggested the crucial role of DH domain in FGD1 function.

Aarskog-scott syndrome (AAS): a case report.

BACKGROUND: Aarskog-Scott syndrome (AAS) is a rare developmental disorder characterised by facial dysmorphism, genital and limb anomalies as well as disproportionate acromelic short stature. Clinical diagnosis is based on physical examination and the presence of the most characteristic clinical signs. The diagnosis can be finally confirmed by molecular tests, which identify mutations in the FGD1 gene. CASE REPORT: The report outlines the orthodontic treatment of a 6-year-old male patient, who was diagnosed with AAS syndrome. He presents all facial and oral clinical signs of this syndrome. The extent of maxillary hypoplasia and early dental crowding are so significant that immediate expansion therapy is required. CONCLUSION: Dental management of patients with AAS syndrome represents a challenge for paediatric dentists. The key to improving a patient's aesthetic, functional and psychological condition is making the correct orthodontic decision.

Aortic root aneurysm in a patient with Aarskog-Scott syndrome.

We present the case of a 69 years old man affected by Aarskog-Scott syndrome. He came to our attention for an aneurysm of the aortic root, with almost moderate aortic regurgitation; moderate mitral regurgitation was discovered during preoperative assessment. We performed a modified Bentall's procedure and mitral valve repair. A patent foramen ovale was closed. Aarskog-Scott syndrome is a complex developmental disorder, characterized by X-linked recessive hereditariness short stature, craniofacial abnormalities, hyperextension of the proximal interphalangeal joints, and genital malformations. Diagnosis is still a challenge, in light of various clinical pictures and features in common with other syndromes (i.e., Noonan, SHORT, and Robinow syndromes). It has been longly debated if cardiac surveillance is needed among the affected patients; it should be probably undertaken, in view of the higher incidence of congenital heart disease. Moreover, the presence of extremely flexible joints suggests the coexistence of a connective tissue disorder.

Novel truncating variants in FGD1 detected in two Danish families with Aarskog-Scott syndrome and myopathic features.

Aarskog-Scott syndrome (AAS) is a developmental disorder, caused by disease-causing hemizygous variants in the FGD1 gene. AAS is characterized by dysmorphic features, genital malformation, skeletal anomalies, and in some cases, intellectual disability and behavioral difficulties. Myopathy has only been reported once in two affected siblings diagnosed with AAS. Only few adult cases have been reported. This article reports four adults with AAS (three male cases and one female carrier) from two unrelated Danish families, all males presented with variable features suggestive of myopathy. All four carried novel hemizygous pathogenic variants in the FGD1 gene; one family presented with the c.2266dup, p.Cys756Leufs*19 variant while the c.527dup; p.Leu177Thrfs*40 variant was detected in the second family. All males had some mild myopathic symptoms or histological abnormalities. Case 1 had the most severe myopathic phenotype with prominent proximal muscular fatigue and exercise intolerance. In addition, he had multiple deletions of mtDNA and low respiratory chain activity. His younger nephew, case 3, had difficulties doing sports in his youth and had a mildly abnormal muscle biopsy and relatively decreased mitochondrial enzyme activity. The singular case from family 2 (case 4), had a mildly myopathic muscle biopsy, but no overt myopathic symptoms. Our findings suggest that myopathic involvement should be considered in AAS.

Genital defects seen in sons of men taking major diabetes drug.

Large study hints that taking metformin before conception could raise risk of birth defects by affecting sperm.

[Analysis of FGD1 gene variant in a child with Aarskog-Scott syndrome].

OBJECTIVE: To detect pathogenic variant of the FGD1 gene in a boy with Aarskog-Scott syndrome. METHODS: Genetic variant was detected by high-throughput sequencing. Suspected variant was verified by Sanger sequencing. The nature and impact of the candidate variant were predicted by bioinformatic analysis. RESULTS: The child was found to harbor a novel c.1906C>T hemizygous variant of the FGD1 gene, which has led to conversion of Arginine to Tryptophane at codon 636(p.Arg636Trp). The same variant was found in his mother but not father. Based on the American College of Medical Genetics and Genomics guidelines, the c.1906C>T variant of FGD1 gene was predicted to be likely pathogenic(PM1+PM2+PM5+PP2+PP3+PP4). CONCLUSION: The novel c.1906C>T variant of the FGD1 gene may underlay the Aarskog-Scott syndrome in this child. Above finding has enabled diagnosis for the boy.

ADAMTS18 deficiency leads to preputial gland hypoplasia and fibrosis in male mice.

ADAMTSs (A disintegrin and metalloproteinase with thrombospondin motifs) are a family of 19 secreted zinc metalloproteinases that play a major role in the assembly and degradation of the extracellular matrix (ECM) during development, morphogenesis, tissue repair, and remodeling. ADAMTS18 is a poorly characterized member of the ADAMTS family. Previously, ADAMTS18 was found to participate in the development of female reproductive tract in mice. However, whether ADAMTS18 also plays a role in the development of male reproductive system remains unclear. In this study, Adamts18 mRNA was found to be highly expressed in the basal cells of the developing preputial gland. Male Adamts18 knockout (Adamts18-/-) mice exhibit abnormal preputial gland morphogenesis, including reduced size and sharp outline. Histological analyses of preputial gland from 2-week-old male Adamts18-/- mice showed significant atrophy of the whole gland. Preputial glands from 7 months and older Adamts18-/- mice appeared macroscopic swelling on their surface. Histologically, preputial gland swelling is characterized by tissue fibrosis and thicker keratinized squamous cell layer. Preputial gland lesions in age-matched male Adamts18+/+ mice were barely detected. ADAMTS18 deficiency does not lead to significant changes in morphogenesis of prostate and testis in male mice. These results indicate that ADAMTS18 is required for normal morphogenesis and homeostasis of the preputial gland in male mice.

Association of antimullerian hormone with the size of the appendix testis, the androgen and estrogen receptors and their expression in the appendix testis, in congenital cryptorchidism.

OBJECTIVES: Antimullerian hormone (AMH) causes regression of the mullerian ducts in the male fetus. The appendix testis (AT) is a vestigial remnant of mullerian duct origin, containing both androgen (AR) and estrogen (ER) receptors. The role of both AMH and AT in testicular descent is yet to be studied. We investigated the possible association of AMH with AT size, the AR and ER, and their expression in the AT, in congenital cryptorchidism. METHODS: A total of 26 patients with congenital unilateral cryptorchidism and 26 controls with orthotopic testes were investigated, and 21 ATs were identified in each group. AMH and insulin-like three hormone (INSL3) concentrations were measured with spectrophotometry. AR and ER receptor expression was assessed with immunohistochemistry using monoclonal antibodies R441 for AR and MAB463 for ER. For the estimation of receptor expression, the Allred Score method was used. RESULTS: AMH concentrations did not present significant differences between patients with congenital cryptorchidism and the controls. Also, no correlation was found between AMH, INSL3, and AT length. Allred scores did not present significant differences. However, expression percentiles and intensity for both receptors presented significant differences. Three children with cryptorchidism and the highest AMH levels also had the highest estrogen receptor scores in the AT. CONCLUSIONS: No association was found between AMH and the studied major parameters. However, higher AMH concentrations, in combination with higher estrogen receptor scores in the AT, may play a role in cryptorchidism in some children. Larger population samples are needed to verify this observation.

A novel truncating variant in the FGD1 gene associated with Aarskog-Scott syndrome in a family previously diagnosed with Tel Hashomer camptodactyly.

Tel Hashomer camptodactyly syndrome is a long-known entity characterized by camptodactyly with muscular hypoplasia, skeletal dysplasia, and abnormal palmar creases. Currently, the genetic basis for this disorder is unknown, thus there is a possibility that this clinical presentation may be contained within another genetic diagnosis. Here, we present a multiplex family with a previous clinical diagnosis of Tel Hashomer camptodactyly syndrome. Whole exome sequencing and pedigree-based analysis revealed a novel hemizygous truncating variant c.269_270dup (p.Phe91Alafs*34) in the FGD1 gene (NM_004463.3) in all three symptomatic patients, congruous with a diagnosis of Aarskog-Scott syndrome. Our report adds to the limited data on Aarskog-Scott syndrome, and emphasizes the importance of unbiased comprehensive molecular testing toward establishing a diagnosis for genetic syndromes with unknown genetic basis.

The Prevalence of Clinical Features in Patients with Aarskog-Scott Syndrome and Assessment of Genotype-Phenotype Correlation: A Systematic Review.

Aarskog-Scott syndrome is a genetically and clinically heterogeneous rare condition caused by a pathogenic variant in the FGD1 gene. A systematic review was carried out to analyse the prevalence of clinical manifestations found in patients, as well as to evaluate the genotype-phenotype correlation. The results obtained show that clinical findings of the craniofacial, orthopaedic, and genitourinary tract correspond to the highest scores of prevalence. The authors reclassified the primary, secondary, and additional criteria based on their prevalence. Furthermore, it was possible to observe, in accordance with previous reports, that the reported phenotypes do not present a direct relation to the underlying genotypes.

Ontogeny of estrogen receptors in human male and female fetal reproductive tracts.

This paper reviews and provides new observations on the ontogeny of estrogen receptor alpha (ESR1) and estrogen receptor beta (ESR2) in developing human male and female internal and external genitalia. Included in this study are observations on the human fetal uterine tube, the uterotubal junction, uterus, cervix, vagina, penis and clitoris. We also summarize and report on the ontogeny of estrogen receptors in the human fetal prostate, prostatic urethra and epididymis. The ontogeny of ESR1 and ESR2, which spans from 8 to 21 weeks correlates well with the known "window of susceptibility" (7-15 weeks) for diethylstilbestrol (DES)-induced malformations of the human female reproductive tract as determined through examination of DES daughters exposed in utero to this potent estrogen. Our fairly complete mapping of the ontogeny of ESR1 and ESR2 in developing human male and female internal and external genitalia provides a mechanistic framework for further investigation of the role of estrogen in normal development and of abnormalities elicited by exogenous estrogens.

Analysis of FGD1 gene variant in a child with Aarskog-Scott syndrome / 中华医学遗传学杂志

OBJECTIVE@#To detect pathogenic variant of the FGD1 gene in a boy with Aarskog-Scott syndrome.@*METHODS@#Genetic variant was detected by high-throughput sequencing. Suspected variant was verified by Sanger sequencing. The nature and impact of the candidate variant were predicted by bioinformatic analysis.@*RESULTS@#The child was found to harbor a novel c.1906C>T hemizygous variant of the FGD1 gene, which has led to conversion of Arginine to Tryptophane at codon 636(p.Arg636Trp). The same variant was found in his mother but not father. Based on the American College of Medical Genetics and Genomics guidelines, the c.1906C>T variant of FGD1 gene was predicted to be likely pathogenic(PM1+PM2+PM5+PP2+PP3+PP4).@*CONCLUSION@#The novel c.1906C>T variant of the FGD1 gene may underlay the Aarskog-Scott syndrome in this child. Above finding has enabled diagnosis for the boy.

The First Korean Family with Aarskog-Scott Syndrome Harboring a Novel Mutation in FGD1 Diagnosed via Targeted Gene Panel Sequencing.

Aarskog-Scott syndrome (AAS), also known as faciogenital dysplasia (FGD, OMIM # 305400), is an X-linked recessive inheritance, characterized by short stature, facial dysmorphism, and skeletal abnormalities. We report the clinical and molecular analysis of a family with ASS. A 31-month-old boy and his cousin were initially mistaken for having Noonan syndrome owing to short stature and facial dysmorphism. Considering the family history, we suspected the possibility of an X-linked genetic disease and performed targeted gene panel sequencing; a novel hemizygous variant c.1192-1 G>A in FGD1 was identified in both the proband and his cousin. This is the first report of ASS in Korea. Targeted gene panel sequencing can be an effective tool for diagnosing rare complex syndromes, including ASS.

Surgical treatment and outcome of complete unilateral urinary tract duplication in a dog.

OBJECTIVE: To report the surgical technique and outcome for correction of complete unilateral duplication of the left urinary tract in a dog. ANIMALS: One 7-month-old entire male Jack Russell terrier. STUDY DESIGN: Case report METHODS: A dog was referred for investigation because of urinary incontinence (UI), preputial irritation (pruritus), diphallia, and cryptorchidism. Computed tomography including urethrographic studies revealed a left duplex kidney, double ectopic left ureters, and a duplex urinary bladder comprising two halves separated by a median septum, each of which emptied into a separate urethra which coursed through separate penises. The left testis was abdominally retained. The right upper urinary tract was considered normal, and the right testis was within the scrotum. Left sided ureteronephrectomy was performed, the median bladder septum was ablated, and the left urethra was ligated. The left penis was partially amputated, and the dog was castrated. RESULTS: Urinary incontinence was improved but persisted after surgery. After repeat imaging, revision surgery was performed 3 months later in which the distal stumps of the (left) ectopic ureters were found to be filling with urine from the right urethra. Urinary incontinence resolved after resection of these ureteric stumps from the prostate and complete transection of the left urethra. CONCLUSION: Extensive surgery with resection and correction of urinary tract duplication was successful in resolving UI in this case. Urogenital duplication should be considered a rare cause of UI. The presence of external congenital deformity (eg, diphallia) should alert clinicians to the possibility of significant concurrent internal abnormalities.

Aarskog-Scott syndrome: clinical and molecular characterisation of a family with the coexistence of a novel FGD1 mutation and 16p13.11-p12.3 microduplication.

Aarskog-Scott syndrome (AAS), also known as facio-genital dysplasia or faciodigitogenital syndrome, is a rare genetic disorder clinically characterised by facial, limb and genitalanomalies. Although also autosomal dominance and recessive patterns have been reported, up to now, only an X linked form associated to mutations of the FGD1 gene has been recognised as causative for this syndrome.In this case report, we describe a large Italian family in which three members across three generations show classical features of the syndrome. The youngest patient, the proband, and his mother were both molecularly studied and characterised for the not previously reported variant c.1828C>T (p. Arg610*) in the FGD1 gene but with the classic phenotype of AAS. Additionally, both the proband and his mother present a 2.5 Mb 16p13.11-p12.3 microduplication, a genetic variant still unclear for the phenotypic consequences: the co-occurrence of the two rare conditions is discussed for the possible clinical significance.

MRI in the evaluation of the azoospermic male.

PURPOSE We aimed to show the usefulness of magnetic resonance imaging (MRI) in the evaluation of infertile men and its ability to distinguish obstructive from nonobstructive azoospermia. METHODS Between April 2015 and February 2018, 45 azoospermic men underwent scrotal MRI. We evaluated the images with an emphasis on signal characteristics of the testis and morphologic changes typical for obstruction. Testicular volume (TV), apparent diffusion coefficient (ADC) value, T1 and T2 signal ratios (testis/muscle) were measured for every testis. On the basis of histologic results, patients were divided into two groups: obstructive azoospermia (OA) and nonobstructive azoospermia (NOA). RESULTS Testes of patients in the OA group had significantly lower ADC values (mean 0.876±101 ×10-3 mm2/s) than in the NOA group (mean, 1.114±147 ×10-3 mm2/s). TV was significantly higher in patients with OA (median, 17.61 mL; range, 11.1-38.4 mL) than in those with NOA (median, 10.5 mL; range, 5.2-22.2 mL). ROC analysis showed that both TV and ADC values were highly predictive for distinguishing between OA and NOA patients, with an area under the ROC curve of 0.82 and 0.92 respectively. A cutoff value of ≥12.4 mL could distinguish obstructive from nonobstructive azoospermia with a sensitivity of 92% and specificity of 63%, whereas for ADC measurements a cutoff value of ≥0.952 ×10-3 mm2/s exhibited a sensitivity of 81% and specificity of 90% There was no statistically significant difference in T1 and T2 signal ratios between both groups. Abnormalities typical for obstruction of the male reproductive tract (e.g., dilatation of ejaculatory ducts, prostatic or seminal vesicle cysts) were found in 78% of patients (14/18) in the obstructive group. CONCLUSION Scrotal MRI is a very effective tool for the evaluation of azoospermic men and may provide important information facilitating interventional treatment of infertility.

Comparative effectiveness of imaging modalities for preoperative assessment of anorectal malformation in the pediatric population.

OBJECTIVE: The aim of this study was to compare the accuracy of MRI, colostography/fistulography, and X-ray imaging modalities for preoperative diagnosis of anorectal malformations (ARMs) in pediatric patients. METHODS: This retrospective analysis included a total of 84 pediatric patients with ARMs. Preoperative imaging findings were assessed by 2 radiologists and compared to surgical findings. RESULTS: MRI identified anomalies of the spine in 25 of 84 patients (29.8%), anomalies of the genital system in 7 of 84 patients (8.3%), anomalies of the urinary system in 22 of 84 patients (26.2%), and underdeveloped sphincter muscle complex in 34 of 84 patients (40.5%). In the 44 subjects receiving both MRI and X-ray, MRI was more sensitive in detecting anomalies of spine (18/44 vs. 8/44; P = 0.002), and both correctly identified the distal end of the rectum in 77.3% (34/44) of the cases. In the 24 subjects receiving both MRI and colostography/fistulography, MRI was more accurate in identifying Pena's classification (22/24 vs. 15/24; P = 0.039). Distal end of the rectum was correctly identified in 75.0% (18/24) and 58.3% (14/24) of the cases (P = 0.125). CONCLUSIONS: MRI could clearly reveal fistula anatomy and associated anomalies of ARMs and should be routinely used for preoperative evaluation of ARMs. TYPE OF STUDY: Study of diagnostic test. LEVEL OF EVIDENCE: Level II.

Clinical but Not Histological Outcomes in Males With 45,X/46,XY Mosaicism Vary Depending on Reason for Diagnosis.

CONTEXT: Larger studies on outcomes in males with 45,X/46,XY mosaicism are rare. OBJECTIVE: To compare health outcomes in males with 45,X/46,XY diagnosed as a result of either genital abnormalities at birth or nongenital reasons later in life. DESIGN: A retrospective, multicenter study. SETTING: Sixteen tertiary centers. PATIENTS OR OTHER PARTICIPANTS: Sixty-three males older than 13 years with 45,X/46,XY mosaicism. MAIN OUTCOME MEASURES: Health outcomes, such as genital phenotype, gonadal function, growth, comorbidities, fertility, and gonadal histology, including risk of neoplasia. RESULTS: Thirty-five patients were in the genital group and 28 in the nongenital. Eighty percent of all patients experienced spontaneous pubertal onset, significantly more in the nongenital group (P = 0.023). Patients were significantly shorter in the genital group with median adult heights of 156.7 cm and 164.5 cm, respectively (P = 0.016). Twenty-seven percent of patients received recombinant human GH. Forty-four patients had gonadal histology evaluated. Germ cells were detected in 42%. Neoplasia in situ was found in five patients. Twenty-five percent had focal spermatogenesis, and another 25.0% had arrested spermatogenesis. Fourteen out of 17 (82%) with semen analyses were azoospermic; three had motile sperm. CONCLUSION: Patients diagnosed as a result of genital abnormalities have poorer health outcomes than those diagnosed as a result of nongenital reasons. Most patients, however, have relatively good endocrine gonadal function, but most are also short statured. Patients have a risk of gonadal neoplasia, and most are azoospermic, but almost one-half of patients has germ cells present histologically and up to one-quarter has focal spermatogenesis, providing hope for fertility treatment options.