Analiza variabilnosti genov HBA1 in HBA2 pri družinski eritrocitozi

Hramus, Ida (author), Debeljak, Nataša (mentor), Kunej, Tanja (co-mentor)

Eritrocitoza je bolezensko stanje s povišano koncentracijo eritrocitov. Delimo jo na primarno, z motnjo v kostnem mozgu in na sekundarno, z motnjo izven kostnega mozga. Družinska eritrocitoza (DE) je dedna oblika bolezni, kjer različice nukleotidnega zaporedja genov (EPOR, EGLN1, EPAS1, VHL, EPO, HBB, HBA1, HBA2 in BPGM) vplivajo na zaznavanje koncentracije kisika ali transport le-tega. Gena HBA1 in HBA2 kodirata alfa verige hemoglobina (Hb) in različice nukleotidnega zaporedja na teh genih lahko vodijo v nastanek oblike Hb s povišano afiniteto za kisik. Kisik, vezan na spremenjen Hb, se v tkivih neuspešno sprošča, kar vodi v hipoksijo in povečano tvorbo krvnih celic. Z uporabo podatkovnih zbirk smo pridobili do zdaj znane različice nukleotidnega zaporedja genov HBA povezane z nastankom DE tipa 7 (ECYT7). Vzpostavili smo protokol za določanje različic nukleotidnega zaporedja v genih HBA z uporabo verižne reakcije s polimerazo (PCR) in sekvenciranjem po Sangerju. V raziskavo smo vključili dva bolnika s sumom na družinsko eritrocitozo. Uspešno smo pomnožili in sekvencirali oba paralogna gena, vendar nismo odkrili različic nukleotidnega zaporedja povezanih z ECYT7. Vzpostavili smo protokol za sekvenčno analizo genov HBA1 in HBA2 za bolnike s sumom na družinsko eritrocitozo.

• Language: Slovenian
• Keywords: družinska eritrocitoza, gena HBA1 in HBA2, alfa veriga, hemoglobin, visoka afiniteta hemoglobina do kisika, različice nukleotidnega zaporedja gena
• Work type: Master's thesis/paper
• Typology: 2.09 - Master's Thesis
• Organization: BF - Biotechnical Faculty
• Publisher: [I. Hramus]
• Year: 2021
• PID: 20.500.12556/RUL-125433
• UDC: 606:601.4:575.224.4:616.155.191(043.2)
• COBISS.SI-ID: 59485443
• Publication date in RUL: 17.03.2021

Secondary language

• Language: English
• Title: Analysis of genetic variability of HBA1 and HBA2 in familial erythrocytosis

Abstract

Erythrocytosis is a disease with an increased number of erythrocytes. Primary erythrocytosis is caused by defect within the bone marrow, while secondary by defect outside the bone marrow. Familial erythrocytosis is a disorder with genetic sequence variations in genes (EPOR, EGLN1, EPAS1, VHL, EPO, HBB, HBA1, HBA2 in BPGM) involved in oxygen sensing pathways or oxygen transport. HBA genes encode for the hemoglobin (Hb) alpha chains, and sequence variants in these genes can cause high-affinity Hb forms. The oxygen bound to these variants is not successfully released into the tissue, causing hypoxia of the tissue and increased erythrocyte production. Using databases, we have obtained all known sequence variants causing (Hb) with high affinity to oxygen associated with familial erythrocytosis type 7 (ECYT7). We developed a protocol for identification of sequence variants in the HBA genes using polymerase chain reaction (PCR) and Sanger sequencing. We analyzed two patients with suspected familial erythrocytosis, differentiated between both paralogs but found no sequence variants associated with ECYT7. We established the protocol for sequencing the HBA1 and HBA2 genes in patients with suspected familial erythrocytosis.

• Keywords: familial erythrocytosis, genes HBA1 and HBA2, alfa chain, hemoglobin, high oxygen affinity hemoglobin, gene sequence variant