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Congenital aniridia is a rare panocular disease defined by a national diagnostic and care protocol (PNDS) validated by the HAS. In most cases, it is due to an abnormality in the PAX6 gene, located at 11p13. Aniridia is a potentially blinding autosomal dominant disease with high penetrance. The prevalence varies from 1/40,000 births to 1/96,000 births. Approximately one third of cases are sporadic. Ocular involvement includes complete or partial absence of iris tissue, corneal opacification with neovascularization, glaucoma, cataract, foveal hypoplasia, optic disc hypoplasia and ptosis. These ocular disorders coexist to varying degrees and progress with age. Congenital aniridia manifests in the first months of life as nystagmus, visual impairment and photophobia. A syndromic form such as WAGR syndrome, WAGRO syndrome (due to the risk of renal Wilms tumor) or Gillespie syndrome (cerebellar ataxia) must be ruled out. Systemic associations may include diabetes, due to expression of the PAX6 gene in the pancreas, as well as other extraocular manifestations. Initial assessment is best carried out in a referral center specialized in rare ophthalmologic diseases, with annual follow-up. The management of progressive ocular involvement must be both proactive and responsive, with medical and surgical management. Visual impairment and photophobia result in disability, leading to difficulties in mobility, movement, communication, learning, fine motor skills, and autonomy, with consequences in personal, school, professional, socio-cultural and athletic life. Medico-socio-educational care involves a multidisciplinary team. Disability rehabilitation must be implemented to prevent and limit situations of handicap in activities of daily living, relying on the Commission for the Rights and Autonomy of People with Disabilities (CDAPH) within the Departmental House of People with Disabilities (MDPH). The general practitioner coordinates multidisciplinary medical and paramedical care.

X and Y chromosomes hove evolved from a common proto-chromosome, 300 million years ago. They shore 29 genes, scottered in two homologous regions (PAR1 and PAR2). Ten per cent of humon genetic diseases result from mutations of X-linked genes. Disorders with mental handicap, muscle involvement or infertility ore overrepresented. X chromosome inactivation is a complex epigenetic process. This mechanism keeps a single transcriptionally active chromosome per cell. At fecondotion, in XX embryo, the active X is always the maternal one, with the paternal X is kept inactive. At the time of implantation of a XX egg, inactivation is erased and reinstalled at random in the embryo, except in the germinal cell line, where both X remain inactive, and in placenta, where only the maternal X is expressed. Skewed inactivation of a X in a woman may indicate the presence of a mutated gene on the inactive X. Contrasting with outosomal disorders, the difference between recessivity and dominance is often relative, as heterozygous women con disclose a phenotype comparable to affected males, as a result of random X inactivation.

Until recently, Bardet-Biedl syndrome was considered as a classic autosomal recessive condition. The disorder is defined by the association of the following clinical features: retinitis pigmentosa, polydactyly, obesity, hypogonadism, and possible mental retardation. This syndrome leads to multiple handicaps (visual impairment, complications of obesity, kidney failure, endocrine dysfunction). This condition, apparently clearly defined from a clinical point of view, appears to be genetically heterogenous. To date, six different genes have been identified: BBS1, BBS2, BBS4, BBS6, BBS7 and BBS8. Interestingly, this condition has recently been linked to a failure of cellular ciliogenesis. Moreover, this disorder is characterized by an additional degree of complexity, as it is the first example of triallelic inheritance described in human beings. However, this new finding appears to be less frequent than expected in this syndrome.

Spondylocostal dysostoses represent a group of very rare genetic disorders, characterised by vertebral and costal segmentation defects, sometimes accompanied by visceral malformations. The major gene involved is DLL3, on chromosome 19. A mutation may lead to a somitogenesis defect, with segmentation defect of axial skeleton and deformations. Depending on the nature of the mutation of DLL3, spondylocostal dysostosis is transmitted as an autosomal dominant (less severe) or autosomal recessive trait (often more severe, but non lethal). Spondylocostal dysostoses must not to be confused with the Jarcho-Levin spondylothoracic dysostosis, a severe, autosomal recessive syndrome. Its most typical aspect is the crab-like appearance of the rib cage leading to major respiratory disorders. Death, due to respiratory insufficiency, usually occurs before the age of two, most often during the first few months. At this time, guidelines for treatment do not exist. We report a case of spondylocostal dysosotosis in a patient born to consanguineous turkish parents, and review the clinical and genetic data on that group of skeletal disorders.

Fetal pathology is a recent field in pathological anatomy, knowing at the present time an important technical and theoretical development. However, it is still insufficiently used to resolve cases of fetal death in utero, or peripartum or perinatal. In this paper, we describe the basics and the techniques used during the fetal examination. We underline the values of these techniques for the understanding of failures of pregnancy and for orientation of the genetical advice for future pregnancies.

The XX males represent a proportion of 1/25 of all patients suffering of the Klinefelter syndrome. From a clinical and endocrinological point of view, they exhibit a hypogonadotropic hypogonadism. Isolated cases are rare and familial forms are exceptional. The XX males may be divided in 3 subgroups: 46, XX males with the SRY gene; 46, XX males without the SRY gene and XX/XY mosaics.

We report a family in which Opitz-Frias G syndrome is expressed across 4 generations. The propositus displays hypertelorism, low grade hypospadias, cleft palate and lips and cleft larynx, making the diagnosis of G syndrome very likely. A cousin of his mother discloses similar clefts, vulviform hypospadias, anal imperforation and mental retardation. His clinical appearance fits perfectly the diagnosis of BBB syndrome. A nephew shows ambiguous genitalia and hypertelorism. Authors suggest the lumping of the BBB and the G syndrome.