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1.  The Clinical Spectrum of Homozygous HOXA1 Mutations 
We report nine new individuals from six families who have homozygous mutations of HOXA1 with either the Bosley-Salih-Alorainy Syndrome (BSAS) or the Athabascan Brainstem Dysgenesis Syndrome (ABDS). Congenital heart disease was present in four BSAS patients, two of whom had neither deafness nor horizontal gaze restriction. Two ABDS probands had relatively mild mental retardation. These individuals blur the clinical distinctions between the BSAS and ABDS HOXA1 variants and broaden the phenotype and genotype of the homozygous HOXA1 mutation clinical spectrum.
PMCID: PMC3517166  PMID: 18412118
2.  A novel syndrome of lethal familial hyperekplexia associated with brain malformation 
BMC Neurology  2012;12:125.
Hyperekplexia (HPX) is a rare non-epileptic disorder manifesting immediately after birth with exaggerated persistent startle reaction to unexpected auditory, somatosensory and visual stimuli, and non-habituating generalized flexor spasm in response to tapping of the nasal bridge (glabellar tap) which forms its clinical hallmark. The course of the disease is usually benign with spontaneous amelioration with age. The disorder results from aberrant glycinergic neurotransmission, and several mutations were reported in the genes encoding glycine receptor (GlyR) α1 and β subunits, glycine transporter GlyT2 as well as two other proteins involved in glycinergic neurotransmission gephyrin and collybistin.
The phenotype of six newborns, belonging to Saudi Arabian kindred with close consanguineous marriages, who presented with hyperekplexia associated with severe brain malformation, is described. DNA samples were available from two patients, and homozygosity scan to determine overlap with known hyperkplexia genes was performed.
The kindred consisted of two brothers married to their cousin sisters, each with three affected children who presented antenatally with excessive fetal movements. Postnatally, they were found to have microcephaly, severe hyperekplexia and gross brain malformation characterized by severe simplified gyral pattern and cerebellar underdevelopment. The EEG was normal and they responded to clonazepam. All of the six patients died within six weeks. Laboratory investigations, including metabolic screen, were unremarkable. None of the known hyperkplexia genes were present within the overlapping regions of homozygosity between the two patients for whom DNA samples were available.
We present these cases as a novel syndrome of lethal familial autosomal recessive hyperekplexia associated with microcephaly and severe brain malformation.
PMCID: PMC3488335  PMID: 23101555
Hyperekplexia; Microcephaly; Simplified gyral pattern; Cerebellar underdevelopment; Autosomal recessive
3.  Molecular and neurological characterizations of three Saudi families with lipoid proteinosis 
BMC Medical Genetics  2011;12:31.
Lipoid proteinosis is a rare autosomal recessive disease characterized by cutaneous and mucosal lesions and hoarseness appearing in early childhood. It is caused by homozygous or compound heterozygous mutations in the ECM1 gene. The disease is largely uncharacterized in Arab population and the mutation(s) spectrum in the Arab population is largely unknown. We report the neurologic and neuroradiologic characteristics and ECM1 gene mutations of seven individuals with lipoid proteinosis (LP) from three unrelated consanguineous families.
Clinical, neurologic, and neuro-ophthalmologic examinations; skin histopathology; brain CT and MRI; and sequencing of the fullECM1 gene.
All seven affected individuals had skin scarring and hoarseness from early childhood. The two children in Family 1 had worse skin involvement and worse hoarseness than affected children of Families 2 and 3. Both children in Family 1 were modestly mentally retarded, and one had typical calcifications of the amygdalae on CT scan. Affected individuals in Families 2 and 3 had no grossneurologic, neurodevelopmental, or neuroimaging abnormalities. Skin histopathology was compatible with LP in all three families. Sequencing the full coding region of ECM1 gene revealed two novel mutationsin Family 1 (c.1300-1301delAA) and Family 2 (p.Cys269Tyr) and in Family 3 a previously described 1163 bp deletion starting 34 bp into intron 8.
These individuals illustrate the neurologic spectrum of LP, including variable mental retardation, personality changes, and mesial temporal calcificationand imply that significant neurologic involvement may be somewhat less common than previously thought. The cause of neurologic abnormalities was not clear from either neuroimaging or from what is known about ECM1 function. The severity of dermatologic abnormalities and hoarseness generally correlated with neurologic abnormalities, with Family 1 being somewhat more affected in all spheres than the other two families. Nevertheless, phenotype-genotype correlation was not obvious, possibly because of difficulty quantifying the neurologic phenotype and because of genetic complexity.
PMCID: PMC3050790  PMID: 21349189
4.  Pictorial Essay: Infants of diabetic mothers 
About 3 to 10% of pregnancies are complicated by glycemic control abnormalities. Maternal diabetes results in significantly greater risk for antenatal, perinatal, and neonatal morbidity and mortality, as well as congenital malformations. The number of diabetic mothers is expected to rise, as more and more of the obese pediatric female population in developed and some developing countries progresses to childbearing age. Radiologists, being part of the teams managing such pregnancies, should be well aware of the findings that may be encountered in infants of diabetic mothers. Timely, accurate, and proper radiological evaluation can reduce morbidity and mortality in these infants. The purpose of this essay is to illustrate the imaging findings in the various pathological conditions involving the major body systems in the offspring of women with diabetes
PMCID: PMC2963757  PMID: 21042439
Birth defects; diabetic mothers; maternal diabetes
5.  A practical discussion to avoid common pitfalls when constructing multiple choice questions items 
This paper is an attempt to produce a guide for improving the quality of Multiple Choice Questions (MCQs) used in undergraduate and postgraduate assessment. Multiple Choice Questions type is the most frequently used type of assessment worldwide. Well constructed, context rich MCQs have a high reliability per hour of testing. Avoidance of technical items flaws is essential to improve the validity evidence of MCQs. Technical item flaws are essentially of two types (i) related to testwiseness, (ii) related to irrelevant difficulty. A list of such flaws is presented together with discussion of each flaw and examples to facilitate learning of this paper and to make it learner friendly. This paper was designed to be interactive with self-assessment exercises followed by the key answer with explanations.
PMCID: PMC3045096  PMID: 21359033
Pitfalls; assessment; student

Results 1-5 (5)