The Marshall syndrome: report of a new family and review of the literature

The genetics and disease mechanisms of rhegmatogenous retinal detachment

Rhegmatogenous retinal detachment (RRD) is a sight threatening condition that warrants immediate surgical intervention. To date, 29 genes have been associated with monogenic disorders involving RRD. In addition, RRD can occur as a multifactorial disease through a combined effect of multiple genetic variants and non-genetic risk factors. In this review, we provide a comprehensive overview of the spectrum of hereditary disorders involving RRD. We discuss genotype-phenotype correlations of these monogenic disorders, and describe genetic variants associated with RRD through multifactorial inheritance. Furthermore, we evaluate our current understanding of the molecular disease mechanisms of RRD-associated genetic variants on collagen proteins, proteoglycan versican, and the TGF-β pathway. Finally, we review the role of genetics in patient management and prevention of RRD. We provide recommendations for genetic testing and prophylaxis of at-risk patients, and hypothesize on novel therapeutic approaches beyond surgical intervention.

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.

Novel Mutation in the COL11A1 Gene Causing Marshall-Stickler Syndrome in Three Generations of a Bulgarian Family

Here we report the first familial case spread through at least three generations, genetically verified cases of Marshall-Stickler syndrome in Bulgaria. The proband, a 2-year-old girl, has craniofacial dysplasia, ocular hypertelorism, small saddle nose with a flat bridge and midface hypoplasia. The pedigree of the proband’s family showed that her father has the same clinical manifestations of the disease. In addition, her father presented with a tall, thin stature and mild hearing loss, manifested with aging. The same dysmorphological symptoms were presented by the paternal grandfather. Both patients, the 2-year-old girl and her father, have been diagnosed to carry Marshall-Stickler syndrome. The COL2A1 gene tested negative in the family. Based on the higher percentage of mutations in the COL2A1 gene, we analyzed this gene as the first target in the family. The COL2A1 gene tested negative, and we sequenced the gene further. A novel splice site mutation c.3474+1G>A was found in intron 44. This variant is related to the clinical presentation in the patient and her father. The c.3474+1G>A mutation results in altered splicing affects at the donor splice site of intron 44, which most probably gives a nonfunctional protein. The variant affects the major triple-helical domain that represents a mutation hot-spot for the gene.

Audiologic Manifestations of Marshall Syndrome

OBJECTIVE

Marshall syndrome is a genetic disorder caused by mutations in the COL11A1 gene. This syndrome is characterized by skeletal, ophthalmologic, craniofacial, and auditory abnormalities. Hearing loss is among the main manifestations reported in this disorder being observed in approximately 80% of affected individuals.The present study aims to describe the audiologic characteristics of three members of a family with Marshall syndrome and also serves as a review of the literature.

STUDY DESIGN

Family study.

SETTING

Tertiary care otology and skull base center.

PATIENTS

We report the audiologic findings in a family with Marshall syndrome consisting of a mother and her son and daughter.

INTERVENTION(S)

The audiologic evaluation included tympanometry, acoustic reflexes testing, auditory brainstem response, transient otoacoustic emissions, pure-tone audiometry, speech audiometry in quiet, and conditioned play audiometry. These methods were applied according to the age of the patients. In addition, we provide a review of the English-language literature in an attempt to clarify the auditory phenotype of this syndrome.

RESULTS

All 3 affected individuals had heterozygous c.3816+1G>A mutation in the splicing donor site of intron 50 of the COL11A1 gene. All three patients in our study had bilateral sensorineural hearing loss. Hearing impairment ranged from mild to moderate in the daughter, moderate in the son, and from mild to moderate in their mother.

CONCLUSION

The majority of individuals with Marshall syndrome present early-onset bilateral sensorineural hearing loss. Hearing impairment is usually detected in early childhood, progresses gradually, and becomes stable in late adulthood, with a severity ranging from mild to severe.

Marshall syndrome: further evidence of a distinct phenotypic entity and report of new findings

Marshall syndrome and type II Stickler syndrome are caused by mutations in COL11A1, which codes for the proα1chain of collagen XI. Collagen XI is a minor fibrillar collagen co-expressed with collagen II in cartilage and the vitreous of the eye. Characteristic features of Marshall syndrome include midfacial hypoplasia, high myopia, and sensorineural-hearing deficit. Deletions, insertions, splice site, and missense mutations in COL11A1 have been identified in Stickler syndrome and Marshall syndrome patients. In this study, we describe the clinical presentations of seven patients with Marshall syndrome from three unrelated Saudi families, inherited as autosomal dominant (two families) and autosomal recessive (one family). Cardinal clinical features of Marshall syndrome are manifested in all patients. One patient had ectodermal abnormalities. Mutations (c.2702G > A in exon 34,IVS50 + 1G > A, and IVS50 + lG > C) were identified in COL11A1 in affected members. Interestingly, the first report of autosomal recessive Marshall syndrome was from Saudi Arabia caused by the same mutation (c.2702G > A, p.Gly901Glu) as in one of our families. This study depicts detailed phenotypic and genetic description of dominant and recessive forms of Marshall syndrome due to COL11A1 mutations.

A loss of function mutation in the COL9A2 gene causes autosomal recessive Stickler syndrome

Stickler syndrome is characterized by ocular, auditory, skeletal, and orofacial abnormalities. We describe a family with autosomal recessive Stickler syndrome. The main clinical findings consisted of high myopia, vitreoretinal degeneration, retinal detachment, hearing loss, and short stature. Affected family members were found to have a homozygous loss-of-function mutation in COL9A2, c.843_c.846 + 4del8. A family with autosomal recessive Stickler syndrome was previously described and found to have a homozygous loss-of-function mutation in COL9A1. COL9A1, COL9A2, and COL9A3 code for collagen IX. All three collagen IX α chains, α1, α2, and α3, are needed for formation of functional collagen IX molecule. In dogs, two causative loci have been identified in autosomal recessive oculoskeletal dysplasia. This dysplasia resembles Stickler syndrome. Recently, homozygous loss-of-function mutations in COL9A2 and COL9A3 were found to co-segregate with the loci. Together the data from the present study and the previous studies suggest that loss-of-function mutations in any of the collagen IX genes can cause autosomal recessive Stickler syndrome.

[Anhidrotic ectodermal dysplasia: report of one case at Mother and Child Center of Chantal Biya Foundation, Yaounde, Cameroon]

Ectodermal dysplasia are rare genetic diseases characterized by the absence or dysplasia of some tissues of ectodermal origin. We present a case of a young boy seen at the age of seven and a half years for late eruption of teeth, morphologic abnormalities of the teeth and a feeling of exaggerated heat. The diagnosis of anhidrotic ectodermal dysplasia was discussed. The absence of sweat glands on the skin biopsy slides was in favor of the diagnosis. Dental prostheses were put in place which the aim of permitting the child to eat normally and have a better self image.

[Anhidrotic ectodermal dysplasia: "congenital ameibomia"]

Anhidrotic ectodermal dysplasia is a congenital, generally X-linked dermatosis that associates facial dysmorphy, short stature, and severe blepharitis. The anomalies of the skin are epidermic abnormalities; reduction of the glands of the derm, particularly the sweat glands, explaining the hypohidrosis; onychodysplasia; trichodysplasia; and abnormal dentition. The ophthalmologic manifestations are palpebral anomalies with a reduction in or an absence of Meibomian glands, dysfunction of the Moll and Zeis glands, leading to chronic squamous blepharitis and lacrimal punctal atresia. These anomalies result in severe attacks of the ocular surface, developing during the second decade, which are often invalidating and require a rigorous follow-up to avoid corneal complications.

A report on 10 new patients with heterozygous mutations in theCOL11A1 gene and a review of genotype–phenotype correlations in type XI collagenopathies

A series of 44 unrelated patients in whom COL2A1 screening demonstrated normal results but whose phenotype was nevertheless highly suggestive of either Stickler syndrome (with ocular involvement) or Marshall syndrome were investigated for mutations in the COL11A1 gene. Heterozygous COL11A1 mutations were found in 10 individuals. A splice site alteration (involving introns 47-55) was present in seven cases, with one in intron 50 (c.3816 + 1G > A) occurring in three patients. Two patients had a different deletion, and a missense mutation (Gly1471Asp) was observed in one case. In 4/10 patients the phenotype was classified as Marshall syndrome because of early-onset severe hearing loss and characteristic facial features. These four patients were all heterozygous for a splice site mutation in intron 50. One of these cases had a type 1 vitreous anomaly despite the presence of a COL11A1 mutation. The remaining 6/10 patients had an overlapping Marshall-Stickler phenotype with less pronounced facial features. None of these had a mutation in the hot spot region of intron 50.

Splicing mutations of 54-bp exons in the COL11A1 gene cause Marshall syndrome, but other mutations cause overlapping Marshall/Stickler phenotypes

Stickler and Marshall syndromes are dominantly inherited chondrodysplasias characterized by midfacial hypoplasia, high myopia, and sensorineural-hearing deficit. Since the characteristics of these syndromes overlap, it has been argued whether they are distinct entities or different manifestations of a single syndrome. Several mutations causing Stickler syndrome have been found in the COL2A1 gene, and one mutation causing Stickler syndrome and one causing Marshall syndrome have been detected in the COL11A1 gene. We characterize here the genomic structure of the COL11A1 gene. Screening of patients with Stickler, Stickler-like, or Marshall syndrome pointed to 23 novel mutations. Genotypic-phenotypic comparison revealed an association between the Marshall syndrome phenotype and splicing mutations of 54-bp exons in the C-terminal region of the COL11A1 gene. Null-allele mutations in the COL2A1 gene led to a typical phenotype of Stickler syndrome. Some patients, however, presented with phenotypes of both Marshall and Stickler syndromes.

Clinical and molecular genetics of Stickler syndrome

Stickler syndrome is an autosomal dominant disorder with characteristic ophthalmological and orofacial features, deafness, and arthritis. Abnormalities of vitreous gel architecture are a pathognomonic feature, usually associated with high myopia which is congenital and non-progressive. There is a substantial risk of retinal detachment. Less common ophthalmological features include paravascular pigmented lattice degeneration and cataracts. Non-ocular features show great variation in expression. Children with Stickler syndrome typically have a flat midface with depressed nasal bridge, short nose, anteverted nares, and micrognathia. These features can become less pronounced with age. Midline clefting, if present, ranges in severity from a cleft of the soft palate to Pierre-Robin sequence. There is joint hypermobility which declines with age. Osteoarthritis develops typically in the third or fourth decade. Mild spondyloepiphyseal dysplasia is often apparent radiologically. Sensorineural deafness with high tone loss may be asymptomatic or mild. Occasional findings include slender extremities and long fingers. Stature and intellect are usually normal. Mitral valve prolapse was reported to be a common finding in one series but not in our experience. The majority of families with Stickler syndrome have mutations in the COL2A1 gene and show the characteristic type 1 vitreous phenotype. The remainder with the type 2 vitreous phenotype have mutations in COL11A1 or other loci yet to be identified. Mutations in COL11A2 can give rise to a syndrome with the systemic features of Stickler syndrome but no ophthalmological abnormality.

Genetics and hearing loss: a review of Stickler syndrome

Stickler syndrome is an autosomal dominant multisystem disease. The four most affected systems are craniofacial, skeletal, ocular, and auditory. The manifestations of Stickler syndrome vary considerably among affected individuals. Audiologists and speech-language pathologists should be familiar with the characteristics associated with Stickler syndrome to facilitate early identification and appropriate management.

Marshall syndrome associated with a splicing defect at the COL11A1 locus

Marshall syndrome is a rare, autosomal dominant skeletal dysplasia that is phenotypically similar to the more common disorder Stickler syndrome. For a large kindred with Marshall syndrome, we demonstrate a splice-donor-site mutation in the COL11A1 gene that cosegregates with the phenotype. The G+1-->A transition causes in-frame skipping of a 54-bp exon and deletes amino acids 726-743 from the major triple-helical domain of the alpha1(XI) collagen polypeptide. The data support the hypothesis that the alpha1(XI) collagen polypeptide has an important role in skeletal morphogenesis that extends beyond its contribution to structural integrity of the cartilage extracellular matrix. Our results also demonstrate allelism of Marshall syndrome with the subset of Stickler syndrome families associated with COL11A1 mutations.