3-M syndrome: a report of three Egyptian cases with review of the literature

Abstract

The 3-M syndrome is a rare autosomal recessive disorder. It is characterized by prenatal and postnatal growth retardation associated with characteristic features. In this study, we report on three patients from two unrelated families, including two male sibs, with the characteristic features and radiological findings of the 3-M syndrome. The main features in our cases were low birth weight, short stature, malar hypoplasia, anteverted nostrils with a fleshy nasal tip, long philtrum, pointed full chin, short broad neck, broad chest with transverse grooves of anterior thorax and hyperlordosis. An orodental examination revealed characteristic findings, some of which were not reported before. Prominent premaxilla, hypoplastic maxilla, thick patulous lips, high-arched palate, median fissured tongue, delayed eruption of teeth with enamel hypocalcification and malocclusion were present in our three studied cases. Radiographic studies showed slender long bones and ribs, a narrow pelvis and foreshortened vertebral bodies. Our reported cases are the offspring of healthy consanguineous parents, confirming the autosomal recessive pattern of inheritance in the syndrome. Cases were reported from different countries all over the world. To our knowledge, these are the first reported Egyptian patients with this rare disorder. This syndrome may be underreported because of the phenotypic overlap with other low birth dwarfism syndromes. Recent identification of a gene mutated in some cases of 3-M syndrome will aid diagnosis.

Hip dislocation in 3-M syndrome

“…The main musculoskeletal features described are a prominent trapezius, short thorax, lumbar hyperlordosis (Temtamy et al, 2006), joint hypermobility (generalized or confined to single joints) (Fuhrmann et al, 1972;Miller et al, 1975;Cantu et al, 1981;Winter et al, 1984; Van Goethem and Malvaux, 1987), winged scapulae (Miller et al, 1975;Hennekam et al, 1987), clinodactyly of the fifth finger (Spranger et al, 1976;Temtamy et al, 2006), pes planus, prominent heels (Spranger et al, 1976;Cantu et al, 1981;Winter et al, 1984;Hennekam et al, 1987), thoracic kyphoscoliosis, and elbow dislocation (Hennekam et al, 1987). The main radiographic anomalies include tall vertebral bodies and long slender tubular bones.…”

The Genetics of 3-M Syndrome: Unravelling a Potential New Regulatory Growth Pathway

“…Other facial features include a fleshy tipped nose, pointed chin and long philtrum [2,13,14]. Skeletal abnormalities including relatively tall vertebrae and slender long bones are seen with variable frequency [13,24,25].…”

“…Other facial features include a fleshy tipped nose, pointed chin and long philtrum [2,13,14]. Skeletal abnormalities including relatively tall vertebrae and slender long bones are seen with variable frequency [13,24,25]. Other features commonly associated with 3-M syndrome are a short neck, winged scapulae, short thorax, transverse chest groove, hyperlordosis, developmental dysplasia hip and spina bifida occulta [2,8,12,13,14,15,24,25,26].…”

Clinical utility gene card for: 3M syndrome

“…It is generally reassuringly informative that the disease has been identified. [1][2][3][4][5][6][7][8][9][10][11] …”