A diagnosis of KBG syndrome was made in six unrelated patients. They presented with slight mental retardation, macrodontia, and skeletal abnormalities. Microcephaly, short stature, facial anomalies, and syndactylies were also noted. The diagnostic criteria of the KBG syndrome are discussed.

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The BBB and G syndromes are multiple congenital anomaly (MCA) syndromes characterized by a developmental defect of the midline field. Prominent clinical manifestations are hypertelorism and, in males, hypospadias. Transmission is most likely autosomal dominant in both syndromes. Examination of two new cases and scrutiny of the literature led us to conclude that there are no discriminating qualitative differences between the two conditions. Therefore we propose that they both be designated by the common term "Opitz syndrome."

Background: Joubert syndrome is a recessive neurodevelopmental disorder characterized by clinical and genetic heterogeneity. Clinical hallmarks include hypotonia, ataxia, facial dysmorphism, abnormal eye movement, irregular breathing pattern cognitive impairment and, the molar tooth sign is the pathognomonic midbrain-hindbrain malformation on magnetic resonance imaging. The disorder is predominantly caused by biallelic mutations in more than 30 genes encoding proteins with a pivotal role in morphology and function of the primary cilium. Oligogenic inheritance or occurrence of genetic modifiers has been suggested to contribute to the variability of the clinical phenotype. We report on a family with peculiar clinical spectrum Joubert syndrome molecularly and clinically dissecting a complex phenotype, in which hypogonadism, pituitary malformation and growth hormone deficiency occur as major features. Case presentation: A 7 year-old male was enrolled in a dedicated "Undiagnosed Patients Program" for a peculiar form of Joubert syndrome complicated by iris and retinochoroidal coloboma, hypogonadism pituitary malformation, and growth hormone deficiency. The molecular basis of the complex phenotype was investigated by whole exome sequencing. The concomitant occurrence of homozygosity for mutations in KIF7 and KIAA0556 was identified, and the assessment of major clinical features associated with mutations in these two genes provided evidence that these two independent events represent the cause underlying the complexity of the present clinical phenotype. Conclusion: Beside the clinical variability of Joubert syndrome, co-occurrence of mutations in ciliopathy-associated genes may contribute to increase the clinical complexity of the trait.

Three female cases of the "rigid spine" syndrome are reported and associated with different nosological entities. One patient was affected by congenital muscular dystrophy and one by a morphological pattern of fibre type disproportion with type I atrophy. The third patient showed very peculiar morphological changes on a muscle biopsy specimen resembling a vacuolar myopathy, which is rarely described in association with the rigid spine syndrome. The importance of an adequate investigation of the rigid spine syndrome and the recognition of the presence or absence of cardiomyopathy, if there is to be correct genetic counselling, is discussed.