2658-6533Research Results in Biomedicine2658-653310.18413/2658-6533-2020-6-2-0-12036Genetics<strong>A novel heterozygous variant in exon 32 of the <em>CHD7</em> gene (c.6923C&gt;T) in a Syrian family with Kallmann syndrome</strong><br /> &nbsp;<strong>A novel heterozygous variant in exon 32 of the <em>CHD7</em> gene (c.6923C&gt;T) in a Syrian family with Kallmann syndrome</strong><br /> &nbsp;WafaAbdulsamadWafaAbdulsamadatomic@aec.org.syMoassassFatenMoassassFatenatomic@aec.org.syAlmedaniSuherAlmedaniSuheratomic@aec.org.syLiehrThomasLiehrThomasThomas.Liehr@med.uni-jena.deWilhelmKathleenWilhelmKathleenThomas.Liehr@med.uni-jena.deAs'sadManarAs'sadManaratomic@aec.org.syKnippenbergSarahKnippenbergSarahinfo@amedes-genetics.deGlaubitzRalfGlaubitzRalfinfo@amedes-genetics.deJarjourRami A.JarjourRami A.atomic@aec.org.syAchkarWalid Al.AchkarWalid Al.ascientific@aec.org.sy20206200

Background: Kallmann syndrome (KS) and CHARGE syndrome (CS) are rare heritable disorders in which anosmia and hypogonadotropic hypogonadism co-occur. KS is genetically heterogeneous with at least eight genes being involved in its pathogenesis, whereas CS is caused by autosomal dominant mutations exclusively in CHD7 gene. The majority of CS-cases are sporadic and only few familial cases have been reported. In these families, mosaicism in one parent, as well as parent-to-child transmission of a CHD7 mutation, were described. The aim of the study: To report a paternal transmission of a variant in exon 32 of the CHD7 gene (c.6923C&gt;T) in a familial case originally suggested to be affected by KS. Materials and methods: Five genes associated with KS were analyzed using Sanger sequencing and MLPA in a 17-year-old male. Results: The heterozygous variant leading to a change of amino-acid serine at position 2,308 to leucine was found in father his three children. Conclusion: Overall this report confirms the existence of KS without CS symptoms, caused by a mutation in a gene reported pathogenic only in CS.

Background: Kallmann syndrome (KS) and CHARGE syndrome (CS) are rare heritable disorders in which anosmia and hypogonadotropic hypogonadism co-occur. KS is genetically heterogeneous with at least eight genes being involved in its pathogenesis, whereas CS is caused by autosomal dominant mutations exclusively in CHD7 gene. The majority of CS-cases are sporadic and only few familial cases have been reported. In these families, mosaicism in one parent, as well as parent-to-child transmission of a CHD7 mutation, were described. The aim of the study: To report a paternal transmission of a variant in exon 32 of the CHD7 gene (c.6923C&gt;T) in a familial case originally suggested to be affected by KS. Materials and methods: Five genes associated with KS were analyzed using Sanger sequencing and MLPA in a 17-year-old male. Results: The heterozygous variant leading to a change of amino-acid serine at position 2,308 to leucine was found in father his three children. Conclusion: Overall this report confirms the existence of KS without CS symptoms, caused by a mutation in a gene reported pathogenic only in CS.

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