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Variants of the C19ORF12-gene have been described in patients with spastic paraplegia type 43 and in patients with mitochondrial membrane protein-associated neurodegeneration (MPAN), a subtype of neurodegeneration associated with brain iron accumulation (NBIA). In both subtypes optic atrophy and neuropathy have been frequently described. This case report describes a patient with bilateral optic atrophy and severe distal muscle weakness based on motor neuropathy without involvement of the central nervous system. Exome sequencing revealed a homozygous pathogenic missense variant (c.187G>C;p.Ala63Pro) of the C19ORF12-gene while iron deposits were absent on repeat MR-imaging of the brain, thus showing that peripheral neuropathy and optic neuropathy can be the sole manifestations of the C19ORF12-related disease spectrum whereby iron accumulation in the brain may be absent.

Caudal regression syndrome (CRS) is a rare congenital disorder characterized by developmental abnormalities of caudal spinal segments. To date, the etiology of CRS is unclear; sporadic cases are strongly associated with maternal diabetes, while familiar recurrence is infrequent. We describe in detail the prenatal clinical and sonographic findings of a recently described hereditary caudal regression syndrome, in four fetuses reported to be homozygous for a mutation in the T (brachyury) gene. The syndrome occurred in three consanguineous, but unrelated families, originating from the same geographical area. All affected fetuses had persistence of the notochord in association with abnormal vertebral ossification, sacral agenesis, and bilateral clubfoot. These findings suggest that, in case of prenatal diagnosis of sacral agenesis, an advanced ultrasound examination should assess the vertebral ossification and the rare persistence of the notochord, in order to rule the involvement of the T gene.

Objective To determine the underlying associations in fetuses with forearm anomalies, and to derive a management strategy to improve prenatal diagnosis and parental counselling. Methods A retrospective review of fetal medicine unit records to identify all cases with an absent, short or abnormal radius and/or ulna. Cases with a generalised skeletal dysplasia were excluded. Fetal medicine, maternal, neonatal and, where appropriate, histopathological reports, were reviewed. Results Sixty-six cases were identified. Two were lost to follow-up and subsequently omitted. Chromosomal anomalies accounted for 19 cases (29.7%), genetic syndromes for 19 (29.7%) and isolated forearm defects for 15 cases (23%). A definitive postnatal diagnosis was made in 54 cases (84%). In 45 of the 64 (70%) cases, a correct prenatal diagnosis was made. Cases with bilateral lesions had a significantly higher association with aneuploidy and genetic syndromes, while those with a sonographically isolated unilateral forearm defect had a very low incidence of other underlying pathology. Conclusion Fetuses with bilateral forearm defects or those with unilateral lesions and other abnormalities detected prenatally have a high incidence of aneuploidy and genetic syndromes. Isolated, unilateral lesions usually have a good prognosis. A management strategy is presented to aid accurate prenatal diagnosis and parental counselling. © 2012 John Wiley & Sons, Ltd.

Nuchal translucency (NT) measurement between 11 and 14 weeks' gestation is an undisputed marker for aneuploidies. When conventional karyotyping is normal, enlarged NT is a strong marker for adverse pregnancy outcome, associated with miscarriage, intrauterine death, congenital heart defects, and numerous other structural defects and genetic syndromes. The risk of adverse outcome is proportional to the degree of NT enlargement. Although the majority of structural anomalies are amenable to ultrasound detection, unspecified genetic syndromes involving developmental delay may only emerge after birth. Concern over these prenatally undetectable conditions is a heavy burden for parents. However, following detection of enlarged NT the majority of babies with normal detailed ultrasound examination and echocardiography will have an uneventful outcome with no increased risk for developmental delay when compared to the general population. Counseling should emphasize this to help parents restore hope in normal pregnancy outcome and infant development.

Background The T gene (brachyury gene) is the founding member of the T-box family of transcription factors and is vital for the formation and differentiation of the mesoderm and the axial development of all vertebrates.Results We report here on four patients from three consanguineous families exhibiting sacral agenesis, a persistent notochordal canal and abnormal ossification of the vertebral bodies, and the identification and characterisation of their underlying genetic defect. Given the consanguineous nature and the similarity of the phenotypes between the three families, we performed homozygosity mapping and identified a common 4.1Mb homozygous region on chromosome 6q27, containing T, brachyury homologue (mouse) or T. Sequencing of T in the affected individuals led to the identification of a homozygous missense mutation, p.H171R, in the highly conserved T-box. The homozygous mutation results in diminished DNA binding, increased cell growth, and interferes with the normal expression of genes involved in ossification, notochord maintenance and axial mesoderm development.Conclusions We have identified a shared homozygous mutation in three families in T and linked it to a novel syndrome consisting of sacral agenesis, a persistent notochordal canal and abnormal ossification of the vertebral bodies. We suggest that screening for the ossification of the vertebrae is warranted in patients with sacral agenesis to evaluate the possible causal involvement of T.

Objectives: To assess the screenees’ views on, and the psychological impact of, a family-based genetic screening programme for familial hypercholesterolaemia (FH) and to evaluate non-participation. Methods: Self-administered questionnaires were filled out at the time of screening and after communication of the test result. Non-participants were interviewed by phone. Results: Of the people approached for screening, 2% did not participate. These 2% were not interested, had already been clinically diagnosed, or were afraid of insurance consequences. 677 screenees participated, of whom 215 (32%) tested FH positive. Less than 5% of the screenees were critical of the approach and the information provided. 20% of the screenees expressed feelings of social pressure. Effects on mood were minimal to absent, as were general ‘quality of life’ effects. Conclusions: Screening for FH is highly acceptable to screenees, although social pressure is prevalent. Only a small percentage of people being approached did not participate.

Heterozygous familial hypercholesterolaemia (FH) is a common autosomal dominant inherited metabolic disease with a prevalence of 1 in 500 in most Western countries. 1– 3 People with FH experience an increased risk for coronary artery disease (CAD) and excess mortality especially at a young age. 4, 5 Until recently the diagnosis of FH was based on clinical signs and symptoms alone. These included increased cholesterol concentrations, in particular of LDL-cholesterol, in combination with the presence of tendon xanthoma, corneal arcus, xanthelasmata and a history of early CAD. Frequently FH was diagnosed after a first cardiac event.

Objectives To illustrate how Apert syndrome, a rare autosomal dominant genetic syndrome, can be detected in the second-trimester of pregnancy using 2D ultrasound, and how 3D ultrasound examination may provide parents with a better understanding of the structural defects affecting their baby.Methods Fetal Medicine Unit database searches to identify Apert syndrome cases.Results Five cases of Apert syndrome were suspected in the second-trimester when sonography showed abnormal extremities including syndactyly, and an abnormal skull shape. In 1 case there was increased nuchal translucency with a normal fetal karyotype in the first-trimester. In all cases, a mutation of the FGFR2 gene confirmed the diagnosis of Apert syndrome. 3D ultrasound was used to show parents the extent of the abnormalities of the skull, face and extremities. Parents were counseled by craniofacial surgeons and geneticists.Conclusion Apert syndrome can be accurately suspected in the second-trimester by careful ultrasound examination of the fetus including the extremities and skull shape. 3D ultrasound can be a useful adjunct to 2D examination for parental counseling. Copyright (c) 2007 John Wiley & Sons, Ltd.

Systematic testing for genetically mediated risk factors has emerged recently, including genetic testing of apparently healthy people. The testing will often be organised within screening programmes.1 Although the empirical evidence of the health benefits of such screening can be convincing, the broader consequences of family screening demand guided implementation strategies, including considerations of the effects on quality of life (QoL) and psychological well being.2,3 Familial hypercholesterolaemia (FH) is a genetic disorder, predisposing to coronary artery disease. The estimated frequency of the genetic factor in western countries is 1 in 500 persons.4–6 In about 90%, the associated metabolic defect results in an accumulation of plasma cholesterol and consequent excess CAD mortality.4–8 The availability of DNA diagnosis at an asymptomatic stage and of effective lipid lowering therapy have called for cascade screening.9–14 In 1994, an FH screening programme was started in The Netherlands on a provisional basis, including a parallel, independent evaluation study. The evaluation study addressed not only the uptake and diagnostic procedure, but also the short and long term impact on QoL and psychological well being of the participants of the screening programme. Some evidence on QoL effects of non-genetic screening programmes is available. Early studies on hypertension screening showed adverse effects, which were contradicted later, both on hypertension and cholesterol screening.15–23 In non-genetic cancer screening programmes, participants showed a temporary decline in the psychological domain of QoL.24–26 For example, in breast cancer screening, anxiety and depression following screening were raised but to a subclinical level,27 without lasting adverse psychological effects.28–30 The psychological disturbance of prostate cancer screening was even less.31 In genetic testing, carriers of an autosomal recessive disorder sometimes grow pessimistic about themselves and could grow less optimistic about their future …

The aim of this article is threefold. First, we describe the accuracy of people's risk perception who have been screened on familial hypercholesterolemia (FH) in a family-based screening program. Second, we identify factors that modify risk perception. Finally, we show the influence of risk perception on subsequent preventive behavior. The risk perception of 556 screenees (677 participants, overall response = 82%) was measured by postal questionnaires on three occasions: at screening and 3 days and 7 months after the test result was reported to the patient. Presentation of the risk was precategorized and given both as numerical (1 in x) and as verbal probability. In addition, medication use and attitudes toward gene therapy were determined 7 months after screening. On average, the screenees underestimated their numeric risk of having FH and getting a myocardial infarction (MI). Furthermore, FH-positive screenees perceived that they were at greater risk of MI than FH negatives, and screenees with the highest actual risk used medication more, perceived a greater risk, and opted more often for future gene therapy. Risk perception of having FH was influenced by cholesterol level, while MI risk perception was affected by age, education, cholesterol level, and cardiovascular disease (CVD) in the family. We conclude that FH-positive screenees correctly perceive a higher risk of getting a heart attack than do FH-negative screenees. Screenees did not believe that MI was inevitable, and risk perception was associated with both medication use and the intention to opt for gene therapy, but not with other preventive measures. Thus, genetic risk notification seems to be acceptable and does not lead to aversion to preventive behavior. (C) 2003 Wiley-Liss, Inc