Determination of Repeat Numbers of (CA)n in Mitochondrial D-loop using Polymerase Chain Reaction-single Strand Conformational Polymorphism (PCR-SSCP) / 체질인류학회지

Polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) analysis is a kind of sensitive mutation detection method that has been usually used in field of medical genetics. A single DNA strand with a mutation or nucleotide polymorphism has a different conformation from its wild-type counterpart, and these conformational differences result in different electrophoretic mobility. In previous study of mitochondrial microsatellite instability in 50 uterine leiomyomas, PCR-SSCP showed 4 types of band mobility at (CA)n of the mitochondrial D-loop. In type 1 and 4, positions of the lower single stand of both were same but those of upper strand were different. In sequencing analysis, repeat number of (CA)n in type 1 was 4, 5 in type 2, 6 in type 3, and 4 in type 4, respectively. Without using expensive sequencing analysis, PCR-SSCP method can be used to detect the repeat number of (CA)n in mitochondrial D-loop.

Reevaluation of Single Nucleotide Polymorphism of OCA2 in Koreans / 체질인류학회지

Oculocutaneous albinism type 2 (OCA2) is an autosomal recessive disorder that results from mutations in the P gene, and has approximately 70% function of melanin biosynthesis in the melanocytes. While the overwhelming majority of pigmentation studies have focused on European populations, very little is known about the gene and mechanisms affecting skin lightening in Asian population. The main goal of the study was to test the distribution of three polymorphisms located in a pigmentation candidate gene, OCA2, in a sample of individuals of Koreans (N=250). The genetic markers were selected for polymorphisms that had an allele frequency difference of at least 30% between East Asian populations and European populations. We investigated Minor Allele Frequencies (MAFs) for each of three polymorphisms within OCA2 and reevaluated the difference of the allele frequency along with populations. MAFs of polymorphisms of OCA2 were presented the different frequency in Korean samples (SNP rs1800414 (His615Arg), A allele=38.8%, rs74653330 (Ala481Thr), A allele=0.8% and rs7497270 (intronic polymorphism), C allele=33.4%). While our results had different distributions to European and Caucasians, they showed similar frequencies with East Asian. This study was to reevaluate the distribution of pigmentation candidate gene in Korean samples, further domestic study will aid in developments of the genetic information on worldwide study.

A Pedigree with c.179 Cytosine to Threonine Missense Mutation of SLC12A3 Gene Presenting Gitelman's Syndrome

A 42-year-old man came to the hospital presenting chest discomfort and general weakness. He had come to the hospital with the same symptoms 3 months ago and 12 years prior. His laboratory test showed hypokalemia, hypomagnesemia and hypocalciuria. The arterial blood gas analysis showed hypochloremic metabolic alkalosis. He had an ultrasonography guided renal biopsy, the result was normal at light microscopy and immunofluorescence microscopy. However, a special stain for Na-Cl cotransporter was weakly expressed compared with the control. The patient and his family underwent genetic sequencing about the SLC12A3 gene. He had a homozygous mutation in the 179th nucleotide of Exon 1 on the SLC12A3 gene (p.Thr60Met) and his parents and sisters were diagnosed as carrier state of Gitelman's syndrome (GS). GS is an inherited tubular disorder which presents mild hypokalemia, hypomagnesemia and hypocalciuria. Since the symptoms and laboratory results are not severe, it can go unnoticed by physicians. Herein we present a family with GS, diagnosed by genetic sequencing.

Association between Mitochondrial D-loop Polymorphism and Copy Number / 체질인류학회지

Mitochondria in cancer have genetic instability like genetic mutations or polymorphisms, and D-loop is hot spot region and is suggested its association with cancer prognosis. Genetic variations of D-loop were associated with mitochondrial copy number. In present study, mitochondrial polymorphism in D-loop (D310 and D514) was studied in 108 DNAs from health individuals and its association with mitochondrial copy number was also investigated. In D310 polymorphism, C7 was most common (37.7%, 40/108), and C8 and C9 was found in 32.1% and 30.2%, respectively. In D514 polymorphism, (CA)5 and (CA)4 was shown in 61.4% and 38.6%, respectively. Mitochondrial copy number was increased in 40.7% while it was decreased in 59.3%. There was no association between mitochondrial polymorphism and copy number. Follow-up study should be needed to confirm its change in same individuals.

Molecular genetics of congenital central hypoventilation syndrome and Haddad syndrome

Congenital central hypoventilation syndrome (CCHS) is a disorder of the autonomic nervous system characterized by a decreased response to hypercarbia. CCHS is frequently associated with congenital megacolon; the combination is called Haddad syndrome. CCHS is associated with dysfunction in respiratory features of the autonomic nervous system and with other disorders, including facial deformities, cardiovascular symptoms, and tumors. Patients with CCHS frequently have a mutation in the homeobox protein 2b (PHOX2B) gene. Most mutations involve heterozygous expansion of alanine repeats (GCN). Interestingly, a higher polyalanine repeat number is associated with a more severe clinical phenotype. To clarify the role of PHOX2B in disease pathogenesis, we introduce and review the clinical and molecular features of CCHS and Haddad syndrome.

Gambogic Acid Induced Apoptosis through Activation of Caspase-dependent Pathway in Aortic Smooth Muscle Cells / 체질인류학회지

Gambogic acid (GA) has powerful apoptotic actions. The authors investigated whether GA has apoptotic effects on aortic smooth muscle cells, and compared its potency with that of simvastatin. Smooth muscle cells were isolated from the aortas of Sprague-Dawley rats (4-6 week). Cell purities were confirmed by IF staining using alpha-smooth muscle actin antibody. The IC50 values for cell death by GA and simvastatin were determined using a MTT assay, and the apoptotic effects of 1 microM GA or 30 microM simvastatin (concentrations correspond to IC50 values) were determined after 24 h of treatment using live cell images and by FITC annexin-V and propidium iodide double-staining. In addition, western blotting was used to evaluate apoptosis by quantifying reductions in the expression levels of the PARP and procaspase-3 as well as cleavages of PARP and procaspase-3 after treatment with 1 microM GA or 30 microM simvastatin. The IC50 of GA (1 microM) was lower than that of simvastatin (30 microM). Cell numbers were markedly reduced by both drugs in live cell images. GA (1 microM) produced a higher level of apoptosis than 30 microM simvastatin (26.4+/-2.37% vs. 8.3+/-1.54%, respectively; P<0.05, n=3) by FITC annexin-V & PI double-staining. In addition, 1 microM GA reduced the expressions of PARP, procaspase-3, and Mcl-1 in cells, whereas 30 microM simvastatin did not. Pretreatment with z-VAD-fmk attenuated GA-induced apoptosis and the cleavages of PARP and procaspase-3. The decreased level of Mcl-1 protein induced by GA treatment was recovered by z-VAD-fmk. These results indicate that GA-induced apoptosis was mediated by a caspase-dependent pathway.

Oculocutaneous Albinism Type 1 Diagnosed by Genetic Study in a Newborn Infant / 대한주산의학회잡지

Oculocutaneous Albinism (OCA) is a heterogenous autosomal recessive disorder characterized by defective melanin biosynthesis. Physical findings including white scalp hair and depigmented skin of whole body in newborn infants are important clinical features of OCA 1. We report a newborn case of OCA 1 with two different TYR mutations, and gene defects of the baby revealed to be originated from both parents carriers of OCA.

Evaluation of KRAS let-7 lcs6 Polymorphism in Korean Populations by Pyrosequencing / 체질인류학회지

A single nucleotide polymorphism (SNP) in the 3'-untranslated region of the KRAS oncogene (rs61764370) was recently reported to act as a genetic marker for increased risk of developing human cancers. The frequency of the variant allele is 5.8% in world population, however, there is no study in Korean population with large cases. In present study, we evaluated the KRAS let-7 lcs6 SNP in Korean population for the first time. Genotyping was performed in 178 randomized subjects. DNA was extracted and SNP was evaluated by using PCR and pyrosequencing to identify the T or G allele of the KRAS let-7 lcs6 SNP. As a result, only T allele was found in all subjects and quantitative sequencing result showed that the proportion of G allele was extremely low. This study confirmed that KRAS let-7 lcs6 have only one allele system in Korean population by sensitive and quantitative pyrosequencing for the first time. Its clinical significance should be studied further.

The double retro-aortic left renal vein / 대한해부학회지

The renal veins drain the kidney into the inferior vena cava and unite in a variable fashion to form the renal vein. The left renal vein is normally located in front of the aorta. However, the retro-aortic renal vein may course posterior to the aorta due to embryological developmental anomalies. During educational dissection, a rare variation of the left renal vein was found in a 66-year old male cadaver. The double retro-aortic renal veins coursed behind the aorta to drain into the inferior vena cava. The superior retro-aortic renal vein drained into the inferior vena cava at the lower border of the L2 vertebra, and the inferior retro-aortic renal vein drained into the inferior vena cava at the upper border of the L4 vertebra. Such a variant is rare, and is a clinically important observation which should be noted by vascular surgeons, oncologists, and traumatologists.

Different frequency of the absence of the palmaris longus according to assessment methods in a Korean population / 대한해부학회지

The palmaris longus (PL) is a slender, spindle-shaped weak flexor of the wrist. Congenital absence of the PL is estimated to occur in 15% among individuals worldwide. However, the frequency of its absence varies considerably among different population groups and with different detection techniques. In the present study, the presence of the PL tendon was examined in a Korean population (n=269) using three clinical tests, namely the Traditional Test, Mishra's Test II, and the Gangata Test. We classified subjects into six types based on whether inspection or palpation was required to determine the presence of the PL and flexor carpi radialis. The most reliable test was determined using Kendall's coefficient of concordance. Our results showed that the PL tendon was absent in 4.1% of the subjects in our study, and bilateral and unilateral absences were 2.2% and 1.8%, respectively. Statistical analysis revealed that these tests had similar reliability for assessing the PL tendon, and the Traditional Test showed the highest effectiveness, at 93%. Therefore the Traditional Test was found to be the most effective for revealing the PL in this Korean population.

Haddad Syndrome with PHOX2B Gene Mutation in a Korean Infant

Congenital central hypoventilation syndrome with Hirschsprung's disease, also known as Haddad syndrome, is an extremely rare disorder with variable symptoms. Recent studies described that congenital central hypoventilation syndrome had deep relation to the mutation of the PHOX2B gene in its diagnosis and phenotype. We report a newborn male infant with clinical manifestations of recurrent hypoventilation with hypercapnea and bowel obstruction. These clinical manifestations were compatible with congenital central hypoventilation syndrome and Hirschsprung's disease, and polyalanine 26 repeats in the PHOX2B gene supported the diagnosis of congenital central hypoventilation. We described a first case of Haddad syndrome in Korean and its clinical and genetic characteristics were discussed.

Bilateral variations of the head of the digastric muscle in Korean: a case report / 대한해부학회지

The digastric muscle, as the landmark in head and neck surgery, has two bellies, of which various variations have been reported. In the submental region of a 72-year-old Korean male cadaver, bilateral variations were found in the anterior belly of the digastric muscle. Two accessory bellies, medial to the two normal anterior bellies of the digastric muscle, ran posterior and medially, merging and attaching at the mylohyoid raphe of the mylohyoid muscle. The 3rd accessory belly originated from the right intermediate tendon and ran horizontally, merging the right lower bundle of the right accessory belly and inserted together. These accessory bellies had no connection with the left anterior belly. This unique variation has not been reported in the literature previously, and this presentation will guide clinicians during surgical interventions and radiological diagnoses.

Fluid Attenuated Inversion Recovery (FLAIR) Imaging of the Normal Brain: Comparisons between Under the Conditions of 3.0 Tesla and 1.5 Tesla

OBJECTIVE: The aim of this study was to evaluate the differences in normal brain MRI findings between under 3.0 Tesla (T) and 1.5T MRI conditions with the use of the fluid attenuated inversion recovery (FLAIR) sequences. MATERIALS AND METHODS: Eleven normal adults underwent imaging with the use of the FLAIR sequences on both 1.5T and 3.0T scanners. Two neuroradiologists compared the signal intensity (SI) of the centrum semiovale (CS), pulvinar thalami (PT) and normal iron deposit structures (IDSs) on the 3.0T and 1.5T FLAIR images, and they evaluated three MRI findings qualitatively: high SI of CS; low SI of PT; low SI of IDS. We also evaluated signal-to-noise ratios (SNRs) for the CS, PT, red nucleus and cerebellar dentate nucleus on the FLAIR images. RESULTS: Based on qualitative analyses, the 3.0T FLAIR images showed all three MRI findings for all cases. Low SI for the PT in seven cases (64%), high SI of the CS in one case (9%) and low SI of the cerebellar dentate nucleus in one case (9%) were visualized only on 3.0T FLAIR images. The mean SNRs of the PT, red nucleus and dentate nucleus in patients where 3.0T FLAIR imaging was performed were significantly lower as compared with the SNRs on 1.5T FLAIR images. The SNR of the CS was not significantly different between under the two magnetic field strengths (p > 0.05). CONCLUSION: We have demonstrated that normal, high and low SIs of the CS, PT and IDS on 3.0T FLAIR images were depicted more frequently and more prominently as compared with those on 1.5T FLAIR images in normal adult brains.

The Association Study of Kir6.2 E23K Polymorphism and Fat Distribution in Koreans / 체질인류학회지

Obesity is caused by interactions of energy consumption, amount of food intake, physical activity and etc, and these elements are influenced by genetic factors. Obesity related genes which have been known by now are over 200. One of these is Kir6.2 which forms the pore region of K(ATP) channel, and genetic variation of which may result in altered beta-cell electrical activity, insulin secretion, glucose homeostasis, and increased susceptibility to type 2 diabetes. Therefore, the purpose of this study was to examine the relationship between Kir6.2 E23K polymorphism and fat distribution or metabolic profiles in Korean. A total of 164 patients who visited Dongsan Medical Center Obesity Clinic from February 2004 to December 2005, were enrolled in this study. Screening for Kir6.2 polymorphism carried out by PCR-RFLP analyses. We divided this group into three groups E/E, E/K, K/K. Serum lipid and blood glucose were measured by autoanalyzer. Visceral fat amount and subcutaneous fat by abdominal CT, total fat mass by DEXA were measured. The subjects of E/E, E/K, K/K genotypes were 24, 79, and 61, respectively. The results of ANOVA analysis was that subjects with the K/K genotypes had more visceral fat amount (P<0.05) and higher total cholesterol levels (P<0.05) than E/E subjects group. Visceral fat amount and serum total cholesterol were significantly different according to Kir6.2 E23K polymorphism. Therefore, Kir6.2 polymorphism may act on fat distribution in Koreans.

Variation in the Division of the Axillary Artery : A Case Report / 대한해부학회지

Arterial variations in left upper limb were observed in an embalmed cadaver. The second part of the axillary artery divided into two stems, medial and lateral stems. The lateral stem was deeper than the medial one and the median nerve was located between these two stems. The lateral stem divided into five branches: the subscapular, two anterior circumflex humeral, a posterior circumflex humeral, and profunda brachii arteries. The medial stem adopted its course superficial to the median nerve, and then divided into the ulnar and radial arteries at elbow level. The present authors describe a previously unreported case and discuss the clinical implications of such a variant.

The Accessory Left Colic Artery Arising from the Superior Mesenteric Artery: A Case Report / 대한해부학회지

Anatomical variation in the abdominal aorta is common and extremely important. We found a rare variation of the abdominal aorta in a Korean male cadaver during a routine dissection course. The superior mesenteric artery gives off a small branch for the descending colon, named accessory left colic artery due to its distribution. The inferior mesenteric artery arises normally from the abdominal aorta and supplied the sigmoid colon and the upper part of the rectum. This variation was rare and it has not been reported previously in Korean. Knowledge of the arterial variation in this region is considerable important during abdominal surgery and invasive procedures. The authors describe this previously unreported case and discuss the clinical implications of such a variant with a brief review of the literature.

The Third Head of the Biceps Brachii Muscle Originated from the Pectoralis Major Muscle / 대한해부학회지

During an educational dissection, the supernumerary head of the biceps brachii muscle was found on the left side in a Korean cadaver. The short and long heads were normal: however, the third head originated from the pectoralis major muscle and was inserted into the conjoined tendon of the biceps brachii muscle. The author describes this previously unreported case in Korea and discusses the clinical implications of such a variant.

Evaluation of Single Nucleotide Polymorphism Responsible for the Determination of Earwax Type in Koreans / 체질인류학회지

The ABCC11 gene is a member of the ATP-binding cassette gene family. A single nucleotide polymorphism (SNP) in the ABCC11 gene is associated with the determination of human earwax type. The purpose of this research is to evaluate the allelic frequencies of this gene in Korean population samples. A total of 619 individuals were analyzed by Dde I restriction fragment length polymorphisms (RFLPs). The genotype frequency of dry earwax in Koreans was very high. The proportions of dry/dry genotype found were 99% (99/100) in normal controls; 98.1% (207/211) in patients with schizophrenia; 99% (99/100) in patients with breast cancer; 96% (48/50) patients with uterine myoma; 98.3% (59/60) in obesity subjects; 100% (43/43) in patients with stomach cancer, and 98.2% (54/55) in attention deficit hyperactivity disorder (ADHD) patients. The wet/wet genotype was not found. There were no significant differences in the distribution of earwax genotypes between controls and experimental groups. These results suggest that the frequency of dry earwax are very high, and therefore the SNP determining earwax type will not be useful in genetic studies of the process involved in various diseases or pathologic conditions in Korean populations.

Dopamine Transporter Gene and Dopamine D2, D3, D4 Receptor Gene Polymorphisms in Attention Deficit Hyperactivity Disorder

OBJECTIVES: The aim of this study was to examine the association of attention-deficit hyperactivity disorder (ADHD) in Korean populations with functional polymorphisms of six genes dopamine receptors (Ser311/Cys311 polymorphism, Taq1 A polymorphism, and Taq1 B polymorphism in DRD2, BalI polymorphism in DRD3, and promoter -521 C/T polymorphism and exon III 48 bp repeat polymorphism in DRD4) and one gene in dopamine transporter (DAT1). METHODS: Participants were 58 children with ADHD and 110 control children. The genotypes were determined by PCR. RESULTS: There was a statistically significant difference in genotype frequency of -521 C/T polymorphism within the promoter region of the DRD4 between two groups. Furthermore, in the male group, both genotype and allele frequencies showed statistically significant differences. CONCLUSION: Findings of the study indicate that -521 C/T polymorphism in promoter region of DRD4 appears to be a possible candidate gene for ADHD in Korean population.

The Relationship between the Therapeutic Response to Antipsychotic Drugs and the Dopamine D2, D3, and D4 Receptor Gene Polymorphisms in Korean Schizophrenic Patients

OBJECTIVES: A considerable number of pharmacogenetic studies have been performed in recent years to define the association of antipsychotic drug response with dopamine receptor polymorphisms. The purpose of this study was to investigate the relationship between the therapeutic response to anti-psychotic drugs and the polymorphisms of the dopamine D2, D3, and D4 receptor genes(DRD2, DRD3 and DRD4, respectively). METHODS: We conducted retrospective chart review of 200 consecutively hospitalized patients with the diagnosis of schizophrenia(DSM-IV) who were treated with various antipsychotics(94% atypical antipsychotics) at Bugok National Hospital, Korea. The patients were divided into two groups, responders and non-responders, by responsiveness to antipsychotic drugs according to a four-point scale used in previous studies; responders included moderate to marked responded patients and non-responders included none to minimal responded patients. We analyzed the Ser311Cys polymorphism in the DRD2, the Ser9Gly polymorphism in the DRD3, and the exon III 48 bp repeat polymorphism in the DRD4. RESULTS: Among the total patients of 200, 141(70.5%) were categorized as responders. There were no significant differences in the frequencies of the DRD2, DRD3, and DRD4 alleles and genotypes between responders and non-responders. CONCLUSION: These results suggest that the Ser311Cys polymorphism in the DRD2, the Ser9Gly polymorphism in the DRD3, and the exon III 48bp repeat polymorphism in the DRD4 are not associated with the therapeutic response to antipsychotic drugs in Korean schizophrenic patients. A larger prospective study is needed to elucidate the association between antipsychotic response and dopamine receptor gene polymorphism.