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Fibrocystic breast changes
Paget disease of the breast
Intrauterine growth restriction
Pelvic inflammatory disease
Gestational trophoblastic disease
Germ cell ovarian tumor
Polycystic ovary syndrome
Premature ovarian failure
Sex cord-gonadal stromal tumor
Surface epithelial-stromal tumor
Congenital cytomegalovirus (NORD)
Congenital rubella syndrome
Neonatal herpes simplex
Preeclampsia & eclampsia
Female sexual interest and arousal disorder
Genito-pelvic pain and penetration disorder
Fetal alcohol syndrome
Fetal hydantoin syndrome
Androgen insensitivity syndrome
Hypospadias and epispadias
Benign prostatic hyperplasia
Male hypoactive sexual desire disorder
Amenorrhea: Pathology review
Benign breast conditions: Pathology review
Breast cancer: Pathology review
Cervical cancer: Pathology review
Complications during pregnancy: Pathology review
Congenital TORCH infections: Pathology review
Disorders of sex chromosomes: Pathology review
Disorders of sexual development and sex hormones: Pathology review
HIV and AIDS: Pathology review
Ovarian cysts and tumors: Pathology review
Penile conditions: Pathology review
Prostate disorders and cancer: Pathology review
Sexually transmitted infections: Vaginitis and cervicitis: Pathology review
Sexually transmitted infections: Warts and ulcers: Pathology review
Testicular and scrotal conditions: Pathology review
Testicular tumors: Pathology review
Uterine disorders: Pathology review
Vaginal and vulvar disorders: Pathology review
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Noam, a 33 year old male, comes to the clinic after trying to conceive a baby with his wife for more than a year, with no luck. Noam is very thin and quite tall. Upon physical examination, you notice that his testes are smaller than normal, and he has enlarged breast tissue. In addition, Noam doesn’t seem to have much facial and pubic hair. You decide to run a blood test, which reveals that Noam’s testosterone and inhibin B levels are decreased, while gonadotropin and estrogen are increased. In addition, you perform a karyotype analysis on his cells and find 47 chromosomes, among which there’s two X chromosomes and one Y chromosome.
Next, you see Hadas, a 17 year old girl who’s worried because she hasn’t gotten her first menstrual period yet. The first thing you notice is that Hadas is quite short for her age. Upon physical examination, she has a webbed neck, a broad chest, and poorly developed breasts with widely spaced nipples. In addition, you notice her ring fingers are very short. A blood test shows low estrogen levels and high gonadotropins, and a karyotype analysis reveals only 45 chromosomes, with one X chromosome.
Okay, based on their presentation, both Hadas and Noam seem to have some sort of disorder of sex chromosomes. Now, humans typically have 23 pairs of chromosomes, so 46 total; out of which 22 pairs are autosomal, and 1 pair consists of sex choromosomes, which can be X or Y. Generally, an individual with two X chromosomes, or 46,XX is considered to be genetically female. However, only one X chromosome gets expressed and the other is inactivated through a process called X inactivation or lyonization, becoming a Barr body. On the other hand, an individual with one X and one Y chromosome, or 46,XY is genetically male. And since there’s only one X chromosome to begin with, there’s generally no Barr body.
Now, individuals with sex chromosome disorders have aneuploidy, meaning that there’s a missing or extra sex chromosome. Most often, this results from nondisjunction, which can occur in the egg or sperm cell during meiosis 1 or 2, where a chromosome pair or sister chromatid respectively doesn’t split apart. So the child of this individual could either receive two chromosomes from that parent and one more from the other parent, resulting in trisomy; or no chromosome from that parent and one from the other parent, resulting in monosomy. Less frequently, nondisjunction may occur during mitosis, where a sister chromatid doesn’t separate.
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