English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Tools annual

Global: Zendy Free Plan

Global: Zendy Tools monthly

Global: Zendy Plus monthly

We report a novel homozygous mutation of the LH receptor (LHR) gene in three siblings: two 46XY and one 46XX. The 46XY siblings presented with female external genitalia, primary amenorrhea, and lack of breast development. Hormonal evaluation revealed a markedly elevated LH level with a low testosterone level, which failed to increase after human CG stimulation. Enzymatic deficiencies of testosterone biosynthesis were eliminated as possible etiologies. Histologic analysis of the inguinal gonads in a 46XY sibling revealed no Leydig cells; Sertoli cells, spermatogonia, and primary spermatocytes were seen. The 46XX sibling had female external genitalia, normal breast development, and primary amenorrhea. Hormonal analyses showed markedly elevated LH levels and low plasma 17 beta-estradiol levels. Genetic analysis of the LHR revealed a homozygous missense mutation at exon 11 of the LHR gene. Guanine was replaced by adenine (GAA--&gt;AAA), resulting in a substitution of lysine for glutamic acid (glu) at amino acid position 354 of the receptor. This mutation is located in the extracellular domain adjacent to the first transmembrane helix of the LHR. Glutamic acid at position 354 of the LHR has been highly conserved throughout evolution. Functional analysis of the LHR mutation, using an in vitro mutagenesis-transfection assay, demonstrated complete loss of function, indicated by the lack of cAMP production after human CG stimulation in transfected human embryonic kidney 293 cells. Screening of family members demonstrated heterozygosity for the mutation, indicating autosomal recessive inheritance. Delineation of the specific genetic defect in this family confirms recent reports that a single mutation in the LHR gene causes male pseudohermaphroditism in 46XY subjects and primary amenorrhea in 46XX subjects. More importantly, it also defines a new region of the LHR molecule that is critical for biologic activity.

A Novel Mutation of the Human Luteinizing Hormone Receptor in 46XY and 46XX Sisters1

A Novel Mutation of the Human Luteinizing Hormone Receptor in 46XY and 46XX Sisters¹