Male infertility is mostly caused by acquired adverse factors, but some patients are caused by congenital genetic diseases. So what are the common types of infertility? The following is an introduction to several types of abnormal chromosome infertility for your reference.
Fragile x chromosome syndrome
Patients with fragile x chromosome syndrome have a "fragile" site on the x chromosome, which can cause non random chromosome breaks or fissures under certain special conditions. Patients exhibit mental retardation, special facial features, large testicles, but no fertility.
"This syndrome, also known as primary microtestis, is characterized by a patient with an extra chromosome, 47, XXY, than a normal male.". There are also some patients with chromosome variants of chimeric type. The patients are mostly tall, with sparse bristles and beards, short penises, small testicles, and a castrated body shape. Some patients have male breast development, and sperm is present in the semen.
The incidence rate is about 1: 1000. The patients with this disease have one more Y chromosome than the normal men. Some patients with this disease may have fertility. The adult patients are mainly characterized by high stature, poor intelligence, and anti social personalities such as violent temper and excitability. There may be many variants of the disease, such as XYYY, XYYY, and X/XYYY chimeras.
Infertility caused by autosomal abnormalities
For example, in 1959, Ford first discovered a patient with Down syndrome of trisomy 21, with sexual dysfunction and infertility. The patient's karyotype is 48xXY+2l
Genetic infertility with normal karyotype
For example, Kallman syndrome, also known as hypogonadism with hypoosmia syndrome; Congenital absence of testis; Familial male hypogonadism.