blood absorption. The results show that the normal skin developed a greater skin colour change at the final stage of irradiation. Although the vitiligo-involved site also shows an increase of the area under the curve, the small magnitude of change was not significant to detect pigment formation clinically. Figure 2(b) displays the correlation of the constitutive melanin content of normal skin to the degree of formation of IPD. The amount of constitutive melanin is quantified by an area of differential apparent absorbance between normal and vitiligoinvolved skin at baseline in the spectral range of 390-450 nm in which the soluble fraction of epidermal melanin predominantly contributes to the apparent absorbance. 9 The result shows that the degree of IPD response appears to be related to the constitutive pigment expressed at short wavelengths.In this study, we found that VIS-NIR radiation produces IPD only in normally pigmented skin and that the presence of constitutive pigment is required to induce IPD response. We conclude that the degree of formation of IPD from VIS-NIR radiation is related to the content of constitutive pigment expressed at short wavelengths (390-450 nm). This relation has been confirmed in an ongoing study on healthy subjects with various skin types.

Background: External genital anomalies are among the most common congenital anomalies. Proper early diagnosis and management of genital abnormalities are of great importance to minimize medical, psychological and social complications. Aim: To detect the incidence of external genital anomalies and disorders of sex development (DSD) in Great Cairo and Qalyubiyah governorates. Subjects and Methods: 20,000 newborns and infants up to the age of 6 months coming for compulsory vaccination at primary health care units and centers in Great Cairo and Qalyubiyah governorates were examined in the years 2006–2007 for suspected genital anomalies. Results: There were 187 (93.5/10,000) cases with external genital anomalies among the screened 20,000 participants. Various abnormalities in the form of 46,XY DSD, undescended testis, hydrocele, hypospadias, micropenis, synechia of the labia and other genital anomalies were diagnosed and classified after thorough clinical examination, and hormonal, radiological, and laparoscopic investigations. Conclusion: This first pilot study in Great Cairo and Qalyubiyah governorates showed a relatively high incidence of genital anomalies and DSD. Therefore, we recommend more studies including larger population sizes to detect the actual incidence of genital anomalies and DSD in Egypt in order to serve those patients and their families.

Isodicentric chromosome formation is the most common structural abnormality of the Y chromosome. As dicentrics are mitotically unstable, they are subsequently lost during cell division resulting in mosaicism with a 45,X cell line. We report on six patients with variable signs of disorders of sex development (DSD) including ambiguous genitalia, short stature, primary amenorrhea, and male infertility with azoospermia. Cytogenetic studies showed the presence of a sex chromosome marker in all patients; associated with a 45,X cell line in five of them. Fluorescence in situ hybridization (FISH) technique was used to determine the structure and the breakage sites of the markers that all proved to be isodicentric Y chromosomes. Three patients, were found to have similar breakpoints: idic Y(qter→ p11.32:: p11.32→ qter), two of them presented with ambiguous genitalia and were found to have ovotesticular DSD, while the third presented with short stature and hypomelanosis of Ito. One female patient presenting with primary amenorrhea, Turner manifestations and ambiguous genitalia revealed the breakpoint: idic Y (pter→q11.1::q11.1→pter). The same breakpoint was detected in a male with azoospermia but in non-mosaic form. An infant with ambiguous genitalia and mixed gonadal dysgenesis (MGD) had the breakpoint at Yq11.2: idic Y(pter→q11.2::q11.2→pter). SRY signals were detected in all patients. Sequencing of the SRY gene was carried out for three patients with normal results. This study emphasizes the importance of FISH analysis in the diagnosis of patients with DSD as well as the establishment of the relationship between phenotype and karyotype.

Disorders/differences of sex development (DSD) comprise a group of congenital disorders that affect the genitourinary tract and usually involve the endocrine and reproductive system. The aim of this work was to identify genetic variants responsible for disorders of human urogenital development in a cohort of Egyptian patients. This three‐year study included 225 patients with various DSD forms, referred to the genetic DSD and endocrinology clinic, National Research Centre, Egypt. The patients underwent thorough clinical examination, hormonal and imaging studies, detailed cytogenetic and fluorescence in situ hybridization analysis, and molecular sequencing of genes known to commonly cause DSD including AR, SRD5A2, 17BHSD3, NR5A1, SRY, and WT1. Whole exome sequencing (WES) was carried out for 18 selected patients. The study revealed a high rate of sex chromosomal DSD (33%) with a wide array of cytogenetic abnormalities. Sanger sequencing identified pathogenic variants in 33.7% of 46,XY patients, while the detection rate of WES reached 66.7%. Our patients showed a different mutational profile compared with that reported in other populations with a predominance of heritable DSD causes. WES identified rare and novel pathogenic variants in NR5A1, WT1, HHAT, CYP19A1, AMH, AMHR2, and FANCA and in the X‐linked genes ARX and KDM6A. In addition, digenic inheritance was observed in two of our patients and was suggested to be a cause of the phenotypic variability observed in DSD.

We describe a 2-year-old boy born to healthy, consanguineous parents. He had craniofacial asymmetry with left frontal bossing, midface hypoplasia, proptosis, and low-set ears. In addition, he had curly, light hair, and oval hypomelanotic patches in the abdomen, lower limbs and back and one hyperpigmented patch in the groin without acanthosis nigricans. Cranial three-dimensional CT scan showed right-coronal, sagittal, and lambdoid suture synostoses. His cranial MRI at 2-months of age showed left hemimegalencephaly, hypoplasia of corpus callosum, and an abnormal configuration of hippocampus. In spite of these cranial findings, he had mild developmental delay and his neurological examination showed symmetric strength, tone and reflexes. Apart from febrile seizures, there was no history of epilepsy. The proband developed asymmetric hydrocephalus at the age of 18 months that required third ventriculostomy. Post-operative cranial MRI showed Chiari I- like malformation and asymmetry of cerebral hemispheres but less dysplastic cerebral cortex. Mutation analysis of FGFR3 showed a c.749C > G, p.Pro250Arg substitution. To the best of our knowledge, these manifestations have not been reported in patients with Muenke syndrome.