Allele frequencies and molecular diagnosis in haemophilia A and B patients from russia and from some Asian Republics of the former U.S.S.R.

Abstract

RFLP analysis of some intra- and extra-genic polymorphic sites of Factor VIII (FVIII) and Factor IX (FIX) genes with relevant DNA probes or by polymerase chain reaction (PCR) was carried out in Slavic populations from the European part of Russia and also in the native ethnic groups of Uzbekistan and Kazahstan. The allele frequencies for the HindIII (intron 19) and XbaI (intron 22) polymorphic sites (PSs) in the FVIII gene were very similar in the two populations studied, but different for the intron 13 (CA)n repeat. Significant variations in the TaqI (intron d) and DdeI (intron a) polymorphisms of the FIX gene were evident between the Russian and Asian populations. Two unusual alleles (4.35 and 4.2 kb) for the extragenic PS St14/TaqI were registered in Slavs and one new allele (380 bp) for the DdeI polymorphic site of FIX was discovered in both Asian populations. Altogether, 210 haemophilia A (HA) and 24 haemophilia B (HB) families were subjected to molecular studies. So far, 160 HA and 12 HB families have been found to be informative for DNA analysis. Carrier status was ascertained in 42 HA and 6 HB female relatives, and rejected in 52 and 10 of them, respectively. The origin of some HA and HB mutations was traced with relevant polymorphic markers in several at-risk families. Prenatal diagnosis was accomplished in 28 HA and three HB families, resulting in the identification of 20 affected male fetuses.

A rapid multifluorescent polymerase chain reaction for genetic counselling in Chinese haemophilia A families

“…It was first reported by Lalloz et al [9] that this STR locus had eight different alleles and 91% of females from different populations were heterozygous for this repeat. The HR of this marker varies from 34% to 83% in different ethnic groups [5,10–17]. The lowest HR of 34% was reported by Aseev et al [10] in Slavs, while the highest HR 83.08% was described in Brazilians by Soares et al [11].…”

Intron 22 inversions in the Turkish haemophilia A patients: prevalence and haplotype analysis

“…The Xba I marker in intron 22 was found to be highly polymorphic for all studied populations with an expected heterozygosity ranging from 0.48% for Caucasians, 49% for Chinese, to 50% for Russians and Polynesian [ 10, 23–25]. We found this site to be equally polymorphic in the Turkish population with an expected heterozigosity of 0.5.…”

Untitled

“…Their frequencies are shown in Table II. (CA) 21 and (CA) 22 were the most frequent alleles (16% and 28.6%, respectively). The EH was 83%, and the OH was 41.3%; the high 2 value obtained was probably due to a deficiency of heterozygotes in our population (Table II).…”

“…For the Int13 marker (Fig. 2b), mother I-1 passed the (CA) 22 allele to her son II-1; her daughter II-2 is homozygotic for both parental (CA) 22 alleles and consequently was detected as a carrier. The other daughter, II-3, inherited the upper (CA) 23 maternal allele and the lower (CA) 22 paternal allele and hence is not a carrier.…”