Sperm Chromosomal Abnormalities And The Relationship Between Gene Deletion And Male Infertility Research

BACKGROUND:Many factors can cause male infertility. Some of them are congenital abnormality in urinogenital system, internal hormonal abnormality, infections in reproductive system, obstruction in ductus deferens, varicocele and so on. There are also some genetic factors that cause male infertility. Genetic factors include cellular and molecular genetic factors. Researches show that chromosomal abnormality and molecular genetic abnormality can cause the male infertility. This article investigates male infertility from genetic view.PURPOSE:To investigate the relationship between male infertility and chromosomal abnormalities and the relationship between Gene deletion and male infertilityOBJECTIVE:Investigate semen and blood serum samples taken from Jilin Province Reproductive Medical Research Center. Age of patients ranges from 25 to 40 years.METHODS:Semen samples were collected and examined using WLJY -9000 CASA; peripheral blood samples were also collected and analyzed the karyotype through G banding. Some blood samples were also undergone PCR amplification using ZFX/Y,SY84,SY86,SY127,SY134,SY143,SY152,SY254,SY255,SY157 primer, and were observed AZF a,AZF b,AZF c,AZF d deletion; blood from superficial brachial vein was also collected and was used for the determination of PRL,LH,FSH,T,E2 levels using RIA method. The relationship between chromosomal abnormality and sperm parameter, semen parameter, seminal plasma biochemical indicator was also analyzed. The relationship between AZF deletion and sperm parameter, semen parameter, seminal plasma biochemical indicator was analyzed as well.RESULTS: (1)Azoospermic karyotypes are 47,XXY;46,XY/46,XY;small sized Y;47,XY+21; 46,XY(Y>18);46,XY(Y<21);46,XY(Y=1/2G);46,XY,1qh+;46,XY(Y≥18);46,XY(Y0.05)between normal group and abnormal group. And the degree of liquefaction of normal group is lower than chromosomal abnormality group.(5)Compared with normal group, in chromosomal abnormality group, sperm density, sperm motility, and sperm viability decreased significantly(P<0.05).(6)Compared with normal group, in chromosomal abnormality group, abnormal fructose content decreased significantly(P<0.05); but neutralα-Glucosidase level had no significant change(P>0.05).(7)Compared with normal group, in chromosomal abnormality group, the level of FSH, LH increased significantly (P<0.05); PRL levels also increased, but there was no significant difference (P>0.05); additionally, there was no significant difference (P>0.05) in the T and E2 levels.(8) If the azoospermia deletion site is sY86, the type of AZF a; if the site is sY127,sY134, sY143,the type of AZF b; if the site is sY254,sY255,the type of AZF c; if the site is sY255,the type of AZF c; if the site is sY157, sY254, sY255, the type of AZF c; if the site is sY143,sY254,sY255,the type of AZF b+c; if the site is sY143,sY255, the type of AZF c+d; if the site is sY152, sY254,sY255, the type of AZF c+d; if the site is sY157, sY152, sY254, sY255, the type of AZF c+d; if the site is sY152,sY255, the type of AZF c+d; if the site is sY127,sY157, sY152,sY254,sY255, sY134,sY152,sY254,sY255, the type of AZF b+c+d.(9)If the oligospermia deletion site is sY143, the type of AZF b; if the site is sY254, sY255, the type of AZF c; if the site is sY157, sY254, sY255, the type of AZF c; if the site is sY152, sY254, sY255, the type of AZF c+d; if the site is sY157, sY152, sY254, sY255, the type of AZF c+d.(10)Compared with normal group, AZF deletions group's ejaculate amount decreased significantly. Regarding liquefaction, semen pH, and semen viscosity, there were no significant differences (P>0.05) between these two groups.(11)Compared with normal group the sperm density, sperm viability decreased significantly (P<0.05) in the AZF deletion group, while the there were no significant differences (P<0.05) in sperm motility.(12)Compared with normal group, AZF deletion group's seminal fructose content had no significant difference (P>0.05); however, deletion Group seminal neutralα-Glucosidase was higher than the normal group without any significant difference (P>0.05). Deletion group's PRL, LH was also higher than the normal group, but there was no significant difference (P>0.05); but the deletion group's LH level was higher than the normal group; FSH was also significantly higher than that normal group. Hence, both groups had significant differences (P<0.05); T level had no significant difference (P>0.05) between these two groups.(13)When 10 cases of karyotype abnormality were examined for Y chromosome microdeletion, 4 cases were Klinefelter Syndrome (47,XXY), karyotype of 1 case was 47,XY,+del(Yq12), 1 case was 46,XY/46,XY; Y chromosome deletion was not seen distinctly in some cases because of small size, and indistinct Y chromosome microdeletion were found in the cases with karyotype 45,X,-Y,-13,+t(Y;13)(p1;q10) and 46,XY(1qh+). The karyotype of other two cases was found 46,XX/ 47,XX,+del(Y) (q11)and 45,X,-Y,-15,+t(Y:15)(p?;q11).CONCLUSION:(1) Percentage of abnormal karyotype was 7.52%. Among Karyotype abnormalities in the male infertility patients, azoospermic patients account 89.02%, oligospermic patients account 4.88%. Patients with weak and few sperms account 6.1%.(2) chromosomal abnormalities reduce sperm density, sperm vitality, and its viability significantly; chromosomal abnormalities decrease fructose content of seminal plasma significantly; while increase FSH, LH levels significantly, the level of T is also decreased significantly. Hence, because of significant influence on the sperm parameters, serum plasma biochemistry, and serum reproductive hormones, chromosomal abnormalities can lead to decreased male fertility.(3) Detection rate for AZF deletion is 14.17%. Among azoospermic patients, AZF deletions are found in 43 cases, which account for 84.3% of all gene deletions; among severe oligospermia patients, AZF deletions are found in 8 cases, accounts 15.7% of total gene deletion.(4) Of azoospermic patients, deletion types include: 2.33% AZFa deletions; 2.33% AZF b deletions;18.6% AZF c deletions; 6.98% AZF b+ c deletion; 51.16% AZF d deletions; AZF 18.6% b+c+d deletions. Of Azoospermic patients with site deletion, sY86 deletions account for 2.33%; sY127 deletions account for 20.93%; sY134 deletion account for 4.65%; sY143 deletions account for 9.3%; sY152 deletions account for 69.77%; sY157 deletions account for 41.86%; sY254 deletions account for 88.37%; sY255 deletions account for 95.35%.(5) In severe oligozoospermia patients, the deletion'type includes 12.5% AZF b deletions; 37.5% AZF c deletions; 50% AZF c+d deletions. Of the deletion sites, sY143 deletions accounted for 12.5%; sY152 deletions accounted for 50%; sY157 deletions accounted for 50%; sY254 and sY255 deletions account for 87.5%.(6) AZF deletions can affect sperm density, sperm viability decrease significantly; AZF deletions can affect FSH, LH levels increase significantly, while T levels decrease significantly.(7) Of 10 cases of abnormal karyotype, 2 cases are found with Y chromosome microdeletions, which account 20% of all deletions. In the karyotype, these two cases with Y chromosome microdeletions can be regarded as Y chromosome abnormalities. Hence, karyotype abnormality related to Y chromosome may have close relation with AZF microdeletion.